research papers on chemical technology

Chemical Papers

Chemical Papers is a peer-reviewed journal focusing on basic and applied chemistry and chemical engineering research.

• Vojtech Spiwok

Societies and partnerships

• Institute of Chemistry, Slovak Academy of Sciences

Latest issue

Volume 78, Issue 6

Latest articles

Exploring the optoelectronic and thermoelectric properties of ge 1− x bi x te (at x  = 12% and 24%) using gga and gga + so approximation for renewable energy applications: a dft study.

• Naqash H. Malik
• Qaiser Rafiq
• Saikh Mohammad

Ultrasonic-assisted hydrothermal synthesis of MNCNT-decorated SmCoO 3 perovskite composite: a facile approach for high-performance energy storage applications

• M. Sangeetha
• N. Shobanadevi
• T. A. Sheeba

Biological impacts of imidazoline derivatives

• Arup K. Kabi
• Raghuram Gujjarappa
• Chandi C. Malakar

Comparative simulation studies on the countercurrent multi-stage solid–liquid extraction of soybean oil by ethanol and hexane

• Temitope A. Oshin
• Kingsley E. Abhulimen
• Timothy A. Adekanye

Aminocarbonylation of 2-(N-substituted) 5-iodobenzoates: synthesis of glyoxylamido-anthranilates, their cytotoxicity and molecular modeling study

• Kirill P. Cheremnykh
• Dmitry S. Baev
• Elvira E. Shults

Journal updates

Chemical papers has a twitter/x account.

Transformative (Springer Compact) Agreements

Author academy: trainings for authors, journal information.

• Astrophysics Data System (ADS)
• CAB Abstracts
• Chemical Abstracts Service (CAS)
• Current Contents/Physical, Chemical and Earth Sciences
• Google Scholar
• IFIS Publishing
• Japanese Science and Technology Agency (JST)
• OCLC WorldCat Discovery Service
• Reaction Citation Index
• Science Citation Index Expanded (SCIE)
• Semantic Scholar
• TD Net Discovery Service
• UGC-CARE List (India)

Rights and permissions

Editorial policies

© Institute of Chemistry, Slovak Academy of Sciences

• Find a journal
• Publish with us
• Track your research

Biomedical and Biotechnology

Catalysis and Reaction Engineering

Environment and Sustainability

Math and Computational Systems

Transport and Thermodynamics

Chemical Technology Research Paper Topics

This collection of chemical technology research paper topics  provides the list of 25 potential topics for research papers and an overview article about history of chemical industry and technology.

1. Biopolymers

Biopolymers are natural polymers, long-chained molecules (macromolecules) consisting mostly of a repeated composition of building blocks or monomers that are formed and utilized by living organisms. Each group of biopolymers is composed of different building blocks, for example chains of sugar molecules form starch (a polysaccharide), chains of amino acids form proteins and peptides, and chains of nucleic acid form DNA and RNA (polynucleotides). Biopolymers can form gels, fibers, coatings, and films depending on the specific polymer, and serve a variety of critical functions for cells and organisms. Advances in metabolic engineering, environmental considerations about renewable polymers from nonpetroleum feedstocks, and the expansion in molecular biology and protein engineering tools in general are taking biopolymer synthesis and production in new directions. The opportunity to enhance, alter, or direct the structural features of biopolymers through genetic manipulation, physiological controls, or enzymatic processes provides new routes to novel polymers with specialty functions. The use of biopolymers in commodity and specialty materials, as well as biomedical applications, can be expected to continue to increase with respect to petrochemical-derived materials. The benefit in tailoring structural features is a plus for generating higher performance properties or more specialized functional performance. Biosynthesis and disposal of biopolymers can be considered within a renewable resource loop, reducing environmental burdens associated with synthetic polymers derived from petrochemicals that often require hundreds of years to degrade. In addition, biopolymers can often be produced from low cost agricultural feedstocks versus petroleum supplies and thereby generate value-added products.

Academic Writing, Editing, Proofreading, And Problem Solving Services

Get 10% off with 24start discount code.

Boranes are chemical compounds of boron and hydrogen. During the 1950s, the U.S. government sponsored a major secretive effort to produce rocket and aircraft fuels based on boron hydrides. Much of the information initially available to the U.S. effort was contained in a book written by the German chemist Alfred Stock in 1933. When burned in air, the energy released by various boron hydride compounds, as measured by their heat of combustion, is 20 to 55 percent greater than the energy released by petroleum-based jet fuels. It was expected that this greater energy content of the boron fuels would translate into equivalent higher payloads or ranges for rockets and aircraft. All of the boron fuel manufacturing processes started with the production of diborane, a compound composed of two boron atoms linked to six hydrogen atoms. Initially, this was produced by reacting lithium hydride with boron trifluoride or boron trichloride in diethyl ether as a solvent. This entailed a need to recover and recycle the expensive lithium. A later process produced diborane by reacting sodium borohydride with boron trichloride in the presence of catalytic amounts of aluminum chloride, using a solvent called diglyme.

3. Chemical Process Engineering

The chemical industry expanded dramatically during the twentieth century to become a highly integrated and increasingly influential contributor to the international economy. Its products seeded and fertilized the growth of other new technologies, particularly in the textiles, explosives, transport, and pharmaceutical industries. The industry also became a major supporter of industrial research, especially in the U.S. and Germany. The production of chemicals during the century can be described as a history of products, processes and professions.

The larger scale changes in chemical production can be better understood in terms of processes rather than as discrete products. Indeed, Hardie and Pratt (1966) describe the history of the chemical industry in terms of the history of its processes; that is, the succession of actions that transform raw materials into a new chemical product. Such conversion may involve chemical reactions (e.g., the production of soda alkali and sulfuric acid in the LeBlanc process); physical change (e.g., oxidation by roasting, or distillation by boiling and condensation); or physical manipulation (e.g., by grinding, mixing and extruding).

4. Chemical Warfare

Popular fiction forecast the use of poison gas in warfare from the 1890s. While an effort was made to ban the wartime use of gas at The Hague International Peace Conference in 1899, military strategists and tacticians dismissed chemical weapons as a fanciful notion. The stalemate of World War I changed this mindset. Under Fritz Haber, a chemist at the Kaiser Wilhelm Institute, Germany’s chemical industry began making gas weapons. Compressed chlorine gas in 5730 cylinders was released against French Algerian and Canadian troops at Ypres, Belgium, on April 22, 1915. The gas attack resulted in approximately 3000 casualties, including some 800 deaths. Within months the British and French developed both gas agents of their own and protective gear, ensuring that chemical warfare would become a regular feature of the war.

A variety of lethal and nonlethal chemical agents were developed in World War I. Lethal agents included the asphyxiating gases such as chlorine, phosgene, and diphosgene that drown their victims in mucous, choking off the supply of oxygen from the lungs. A second type were blood gases like hydrogen cyanide, which block the body’s ability to absorb oxygen from red corpuscles. Incapacitating gases included lachrymatorics (tear gases) and vesicants (blistering gases). The most notorious of these is mustard gas (Bis-[2- chloroethyl] sulphide), a blistering agent that produces horrible burns on the exposed skin and destroys mucous tissue and also persists on the soil for as long as 48 hours after its initial dispersion.

5. Chromatography

The natural world is one of complex mixtures, often with up to a 100,000 (e.g., proteins in the human body) or 1,000,000 (e.g., petroleum) components. Separation methods necessary to cope with these, and with the simpler but still challenging mixtures encountered, for example in pharmaceutical analysis, are based on chromatography and electrophoresis, and underpin research, development, and quality control in numerous industries and in environmental, food, and forensic analysis. In chromatography, a sample is dissolved in a mobile phase (initially this was a liquid), which is then passed through a stationary phase (which is either a liquid or a solid) held in a small diameter tube—the ‘‘column.’’ According to the differing relative solubilities in the two phases, mixture components travel through the column at different rates and become separated before emerging and detected by the measurement of some chemical or physical property. The sample size can be as small as one picogram (10–12 g), but tens of grams can be handled in preparative separations.

6. Coatings, Pigments, and Paints

The development and application of pigments, paints, and coatings have been an integral part of human development from Paleolithic cave paintings, the art of early civilizations, and protection of buildings from rain. During the twentieth century, understanding of chemicals and the manufacturing need for high-quality decorative and protective coatings drove rapid progression in paint technology. All paints employ the same basic ingredients: pigment to provide color; a medium to bind or suspend the pigment, including emulsions such as resins or oils; and a solvent carrier, which acts to wet the surface to ensure adhesion and thins the resin to make it easy to apply. Early pigments such as those used in Minoan frescoes and Anasazi rock art and the use of henna as body paint originated primarily from natural sources. Clays, mineral pigments such as iron or chromium oxide, vegetable dyes, animal sources such as shells or urine, as well as precious metals and gems gave rise to a broad selection of pigments that were often unique to one region (e.g., lapis lazuli) and thus highly prized as trade items. But value wasn’t limited merely to pigments. Preservation of painted surfaces required protective resins. The most successful early coating was lacquer, used in China since at least the 1300 BC. Lacquer was processed—using a highly guarded secret formula—from resin from the lacquer tree (Rhus vernicflua). Shellac, produced from the gum secreted by an insect native to India and southern Asia, makes a varnish when mixed with acetone or alcohol and was used from the eighteenth century. Natural plant resins dissolved in oil or solvent such as turpentine were used in the nineteenth century— evaporation of the solvent leaves a lacquer coating.

7. Combinatorial Chemistry

Combinatorial chemistry is a term created about 1990 to describe the rapid generation of multitudes of chemical structures with the main focus on discovering new drugs. In combinatorial chemistry the chemist should perform at least one step of the synthesis in combinatorial fashion. In the classical chemical synthesis, one synthetic vessel (flask, reactor) is used to perform chemical reaction designed to create one chemical entity. Combinatorial techniques utilize the fact that several operations of the synthesis can be performed simultaneously. Historically, the first papers bringing the world’s attention to combinatorial chemistry were published in 1991, but none of these papers used the term combinatorial chemistry. Interestingly, they were not the first papers describing the techniques for preparation of compound mixtures for biological evaluation. Previously, H. Mario Geysen’s lab had prepared mixtures of peptides for identification of antibody ligands in 1986. Other laboratories heavily engaged in synthesizing multitudes or mixtures of peptides were Richard A. Houghten’s laboratory in San Diego and A ´ rpa´d Furka’s laboratory in Budapest. The recollections of the authors of these historical papers were published in the journal dedicated to combinatorial chemistry, Journal of Combinatorial Chemistry.

8. Cracking

Three major innovations emerged to meet the dramatically higher needs for quantity and better quality motor fuel in the twentieth century: thermal cracking, tetra ethyl lead, and catalytic cracking (including the fluid method). William M. Burton of Standard Oil, Indiana, in 1911–1913 raised gasoline fractions from petroleum distillation from 15 to 40 percent by increasing both temperatures and pressures. Benjamin Stillman Jr. of Yale University had discovered in 1855 that high temperatures could transform or ‘‘crack’’ heavy petroleum fractions into lighter or volatile components, but at atmospheric pressure over half of the raw material was lost to vaporization before the cracking temperature (about 360C) was reached. English scientists James Dewar and Boverton Redwood discovered and patented in 1889 a process using higher pressure to restrain more of the heavier fractions and increase the volatile components. Burton and his team, not aware of this patent at the start of their work, similarly used higher pressure to improve his gasoline yields. Their process by 1913 employed a drum 9 by 2.5 meters diameter over a furnace and a long runback pipe of 300 millimeter diameter that carried vapors to condensing coils and simultaneously allowed heavier fractions to drip back into the drum for more cracking. A tank connected to the condensing coils separated gasoline from the uncondensed hydrocarbon vapors. They used a comparatively low (5.1 atmospheres) pressure because they relied on riveted plates. Burton’s team improved the batch process in the next three years with false bottom plates in the still to improve cleaning time of coke deposits, and a bubble tower to improve fractionation of cracked vapors and increase gasoline yield. Refinery manager Edgar M. Clark took cracking to the next step by using tubes of about 100 millimeters diameter as the primary contact with the furnace, which increased cracking time and allowed pressures of about 6.8 atmospheres, and decreased maintenance time because of reduced coke deposition and fuel costs.

9. Detergents

Detergents are cleaning agents used to remove foreign matter in suspension from soiled surfaces including human skin, textiles, hard surfaces in the home and metals in engineering. Technically called surfactants, detergents form a surface layer between immiscible phases, facilitating wetting by reducing surface tension. Detergent molecules have two parts, one of which is water-soluble (lyophobic) and the other oil or fat-soluble (lyophilic). They are adsorbed onto surfaces where they remove dirt by suspending it in foam. Some also act as biocides, but no single product does these things equally well. Special detergents also have many uses in industry and engineering. In the oil industry for example, surfactants are sometimes used to promote oil flow in porous rocks, or to flush out oil left behind by a water flood. In this case a band of detergent is put down before the water to create a low surface tension and thus allow the oil-bearing rock to be scrubbed clean. The water is often made viscous by adding a polymer to prevent it breaking through the surfactant layer. Detergents are also widely used in industrial flotation processes to separate lighter particles from a mixture with heavier materials.

The decade commencing in 1900 marked the end of half a century of remarkable inventiveness in synthetic dyestuffs that had started with William Perkin’s 1856 discovery of the aniline dye known as mauve. The products, derived mainly from coal tar hydrocarbons, included azo dyes, those containing the atomic grouping – N = N -, and artificial alizarin (1869–1870) and indigo (1897). By 1900, through intensive research and development, control of patents, and aggressive marketing, the industry was dominated by German manufacturers, such as BASF of Ludwigshafen, and Bayer, of Leverkusen. A new range of dyes based on anthraquinone (from which alizarin and congeners were made), and generally known as vat dyes, were the first major innovations in the twentieth century. Anthraquinone was obtained by oxidation of the three-ring aromatic hydrocarbon anthracene. Vat dyes are generally applied in reduced, soluble form; they then reoxidize to the original pigment and are extremely stable.

11. Electrochemistry

Electrochemistry deals with the relationship between chemical change and electricity. Under normal conditions, a chemical reaction is accompanied by the liberation or absorption of heat and not of any other form of energy. However, there are many so-called electrochemical reactions that when allowed to proceed in contact with two electronic conductors joined by conducting wires, will generate electrical energy in this external circuit. Current between the electrodes (usually metallic plates or rods) is carried by electrons, while in the electrolyte, a nonmetallic ionic compound either in the molten condition or in solution in water or other solvents, ions carry the current. Conversely, the energy of an electric current can be used to bring about many chemical reactions that do not occur spontaneously. The process in which electrical energy is directly converted into chemical energy is called electrolysis. The products of an electrolytic process have a tendency to react spontaneously with one another, reproducing the substances that were reactants and were therefore consumed during the electrolysis. If this reverse reaction is allowed to occur under proper conditions, a large proportion of the electrical energy used in the electrolysis can be regenerated. This possibility is used in accumulators or storage cells, sets of which are known as storage batteries.

12. Electrophoresis

Electrophoresis is a separation technique that involves the migration of charged colloidal particles in a liquid under the influence of an applied electric field. The word is derived from electro, referring to the energy of electricity, and phoresis, from the Greek verb phoros, meaning ‘‘to carry across.’’ Electrophoresis has many applications in analytical chemistry, particularly biochemistry. It is one of the staple tools in molecular biology and it is of critical value in many aspects of genetic manipulation, including DNA studies, and in forensic chemistry. Swedish biochemist Arne Tiselius carried out studies on proteins and colloids in the 1920s, and in 1930 introduced electrophoresis as a new technique for separating proteins in solution on the basis of their electrical charge. Tiselius was awarded the 1948 Nobel Prize in chemistry for this work, and the technique became a common tool in the 1940s and 1950s. Biological molecules such as amino acids, peptides, proteins, nucleotides, and nucleic acids, possess ionizable groups. At any given pH (concentration of hydrogen ions), these molecules exist in solution as electrically charged species either as cations (positive, or þ) or anions (negative, or ). Depending on the nature of the net charge, the charged particles will migrate either to the cathode or to the anode. For example, proteins in an electric field separate according to size, shape, and charge with charges contributed by the side chains of the amino acids composing the proteins. The charge of the protein depends on the hydrogen ion content of the surrounding buffer with a high ionic strength resulting in a greater charge.

13. Environmental Monitoring

As a dynamic system, the environment is changing continually, with feedback from both natural (climatic or biogeochemical) and anthropogenic (human activities) sources. Assessing the rate and magnitude of environmental processes is difficult, especially as data collection over time is limited to the last century, or even the last few decades. Since the 1980s, environmental monitoring programs have been developed as a response to concerns that environmental impact or sustainability of policy initiatives could not be evaluated adequately. So-called State of the Environment Reports date from this period. Many are concerned with the state of national, regional, or local environments (land, rivers, or seas); others focus on environments at particular risk, mostly due to human impact and pollution (e.g., environmental contaminants in marine or terrestrial wildlife), or those where environmental quality is significant in the context of human health (e.g., urban air quality; water resources, fisheries). Many monitoring programs include information collected remotely by satellites (see Satellites, Environmental Sensing), but this entry focuses on technologies and policies for in situ monitoring. Adequate and sustained monitoring and its evaluation provides early warning of possible environmental degradation. Such information is important for the prediction of change that may be generated in the wake of a development project, such as dam construction or deforestation programs. In this context—as an element of an environmental impact assessment—monitored data are valuable for an evaluation of sustainability.

14. Explosives

All chemical explosives obtain their energy from the almost instantaneous transformation from an inherently unstable chemical compound into more stable molecules. The breakthrough from the 2000- year old ‘‘black powder’’ to the high explosive of today was achieved with the discovery of the molecular explosive nitroglycerine, produced by nitrating glycerin with a mixture of strong nitric and sulfuric acids. Nitroglycerin, because of its extreme sensitivity and instability, remained a laboratory curiosity until Alfred Nobel solved the problem of how to safely and reliably initiate it with the discovery of the detonator in 1863, a discovery that has been hailed as key to both the principle and practice of explosives. Apart from the detonator, Nobel’s major contribution was the invention of dynamite in 1865. This invention tamed nitroglycerine by simply mixing it with an absorbent material called kieselguhr (diatomous earth) as 75 percent nitroglycerin and 25 percent kieselguhr. These two inventions were the basis for the twentieth century explosives industry. Explosives are ideally suited to provide high energy in airless conditions. For that reason explosives have played and will continue to play a vital role in the exploration of space.

15. Feedstocks

The word feedstock refers to the raw material consumed by the organic chemical industry. Sometimes, feedstock is given a more restricted meaning than raw material and thus applied to naphtha or ethylene, but not petroleum. The inorganic chemical industry also consumes raw materials, but the feedstock tends to be specific to the process in question, such as sulfur in the case of sulfuric acid. The development and growth of new feedstocks has driven the evolution of the organic chemical industry over the last two centuries. To a large extent, the history of this industry is the history of its feedstocks. Until the nineteenth century, the only significant raw material for the nascent organic chemical industry was fermentation- based ethanol (ethyl alcohol). Gradually, the products of wood distillation also became important, only to be overshadowed after 1860 by the coal-tar industry. As the organic chemical industry expanded in both size and scope between 1880 and 1930, the need for new feedstocks became urgent. The competition between coal and petroleum was resolved in favor of the latter in the late 1950s. The petrochemical industry has been phenomenally successful, underwriting the postwar boom in organic chemicals and plastics and weathering the oil crises of the 1970s with minimal damage. Its long-term sustainability remains an issue, and increasing attention is being paid to renewable feedstocks.

16. Green Chemistry

The term ‘‘green chemistry,’’ coined in 1991 by Paul T. Anastas, is defined as ‘‘the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances.’’ This voluntary, nonregulatory approach to the protection of human health and the environment was a significant departure from the traditional methods previously used. While historically people tried to minimize exposure to chemicals, green chemistry emphasizes the design and creation of chemicals so that they do not possess intrinsic hazard. Within the definition of green chemistry, the word chemical refers to all materials and matter. Therefore, the application of green chemistry can affect all types of products, as well as the processes to make or use these products. Green chemistry has been applied to a wide range of industrial and consumer goods, including paints and dyes, fertilizers, pesticides, plastics, medicines, electronics, dry cleaning, energy generation, and water purification.

17. Industrial Gases

While the gases that are now commonly referred to as ‘‘industrial,’’ namely oxygen, hydrogen, carbon dioxide, and nitrogen, were not fully understood until the nineteenth century, scientists in the twentieth century moved rapidly to utilize the knowledge. Driven largely by the demands of manufacturing industries in North America and Western Europe, rapid improvements in the technology of production and storage of industrial gases drove what has become a multibillion dollar business, valued at $34 billion in 2000. At the start of the twenty-first century, industrial gases underpin nearly every aspect of the global economy, from agriculture, welding, metal manufacturing and processing, refrigerants, enhanced oil recovery, food and beverage processing, electronic component manufacturing, to rocket propulsion. Oxygen for metal manufacturing is the largest volume market, with chemical processing and electronics using significant volumes of hydrogen and lower volumes of specialty gases such as argon. One of the byproducts of the expansive use of industrial gas is an increase in undesirable environmental pollutants—contributing to the ‘‘greenhouse effect’’ and an overabundance of nitrates from agriculture application. Subsequently, government controls worldwide have led the gas industry to revamp some of its distribution and application. Hydrogen is likely to be the gas of the future, employed in ‘‘green’’ fuel cell technology, and glass and steel manufacturers are reducing nitrous dioxide emissions by mixing oxygen with coal.

18. Isotopic Analysis

Beyond the analysis of the chemical elements in a sample of matter, it is possible to determine the isotopic content of the individual chemical elements. The chemical analysis of a substance generally takes its isotopic composition to be a ‘‘standard’’ that represents terrestrial composition, because for most purposes the isotopic ratios are more or less fixed, allowing chemical weight to be a useful laboratory parameter for most elements. Deviations from the standard composition occur because of differences in: 1. Nuclear synthesis 2. Radioactive decay 3. Geological, biological, and artificial fractionation 4. Exposure to various sources of radiation Applications of isotopic analysis make use of these sources of variation. Our knowledge results from analytical techniques developed during the twentieth century that allow precisions of 10–5 and that have led to significant improvements in the understanding of the Earth and solar system and even of archaeology.

19. Nitrogen Fixation

In 1898, the British scientist William Crookes in his presidential address to the British Association for the Advancement of Science warned of an impending fertilizer crisis. The answer lay in the fixation of atmospheric nitrogen. Around 1900, industrial fixation with calcium carbide to produce cyanamide, the process of the German chemists Nikodemus Caro and Adolf Frank, was introduced. This process relied on inexpensive hydroelectricity, which is why the American Cyanamid Company was set up at Ontario, Canada, in 1907 to exploit the power of Niagara Falls. Electrochemical fixing of nitrogen as its monoxide was first realized in Norway, with the electric arc process of Kristian Birkeland and Samuel Eyde in 1903. The nitrogen monoxide formed nitrogen dioxide, which reacted with water to give nitric acid, which was then converted into the fertilizer calcium nitrate. The yield was low, and as with the Caro–Frank process, the method could be worked commercially only because of the availability of hydroelectricity.

In Germany, BASF of Ludwigshafen was interested in diversification into nitrogen fixation. From 1908, the company funded research into nitrogen fixation by Fritz Haber at the Karlsruhe Technische Hochschule. Haber specialized in the physical chemistry of gas reactions and drew on earlier studies started in 1903 on the catalytic formation of ammonia from its elements, nitrogen and hydrogen. He attacked the problem with high pressures, catalysts, and elevated temperatures. Even under optimum conditions the yield was low, around 5 percent, but Haber arranged for unreacted hydrogen and nitrogen to be recirculated. Though exothermic, the reaction was carried out at 600C in order to increase the rate. The preferred catalyst was either osmium or uranium. The main part of the apparatus was the furnace (later known as a converter) in which the gases were preheated by the outgoing reaction mixture. At a pressure of 200 atmospheres the gases were forced to react in the presence of the catalyst. Cooling moved the equilibrium in the direction of producing ammonia, which was liquefied and separated from unreacted hydrogen and nitrogen.

20. Oil from Coal Process

The twentieth-century coal-to-petroleum or synthetic fuel industry evolved in three stages: 1. Invention and early development of Bergius coal liquefaction (hydrogenation) and Fischer–Tropsch (F–T) gas synthesis from 1910 to 1926. 2. Germany’s industrialization of the Bergius and F–T processes from 1927 to 1945. 3. Global transfer of the German technology to Britain, France, Japan, Canada, the U.S., and other nations from the 1930s to the 1990s. Petroleum had become essential to the economies of industrialized nations by the 1920s. The mass production of automobiles, the introduction of airplanes and petroleum-powered ships, and the recognition of petroleum’s high energy content compared to wood and coal, required a shift from solid to liquid fuels as a major energy source. Industrialized nations responded in different ways. Germany, Britain, Canada, France, Japan, Italy, and other nations, having little or no domestic petroleum, continued to import it. Germany, Japan, and Italy also acquired by force the petroleum resources of other nations during their 1930s–1940s World War II occupations in Europe and the Far East. In addition to sources of naturally occurring petroleum, Germany, Britain, France, and Canada in the 1920s–1940s synthesized petroleum from their domestic coal or bitumen resources, and during the 1930s–1940s war years Germany and Japan synthesized petroleum from the coal resources they seized from occupied nations. A much more favorable energy situation existed in the U.S., and it experienced few problems in making an energy shift from solid to liquid fuels because it possessed large resources of both petroleum and coal.

21. Radioactive Dating

There are natural radioactive isotopes that have half-lives comparable to the age of the earth, the most familiar being uranium-235 and -238(235U, 238U) and thorium-232 (232Th). The decay of these isotopes proceeds sequentially through intermediate products having much shorter half-lives to the stable isotopes of lead, 207Pb, 206Pb, and 208Pb, respectively. There are 14 other isotopes scattered through the periodic table that have half-lives spanning times from 1015 to 109 years. All can be used for dating geologic materials. There are other isotopes, termed cosmogenic isotopes, that are produced by cosmic rays and that have half-lives that are useful for measuring periods of historical interest. The best known of these is carbon-14 (14C), which has important uses in archaeology because of its half-life of 5760 years. Procedures for measuring isotope composition have the disadvantage of destroying the extracted portion of the sample used. The phenomena that allow nondestructive analysis rely on exciting optical radiation or x-radiation from the atoms of the sample, most commonly induced by electron bombardment. In these methods, isotopic effects are too small to be accurately observed.

22. Reppe Chemistry

Reppe chemistry refers to a group of high-pressure reactions used in industry to make various organic chemicals. Most of these reactions were based on acetylene, and as acetylene declined in popularity (because of the cheapness of ethylene) in the 1960s, most of the Reppe reactions have also lost their significance. However, the formation of butanediol from acetylene has survived and is now one of the few acetylene-based processes used in the chemical industry. Walter Reppe who was working for the German firm of IG Farben at Ludwigshafen on the Rhine, discovered in 1932 that alcohols could be added to acetylene under considerable pressure to form the corresponding vinyl ether. The dangers of using acetylene were well known, and the success of this reaction was unexpected. The vinyl ethers were used as the starting point for the production of polyvinyl ethers, which were considered to be possible alternatives to polyvinyl chloride (PVC). Subsequently they turned out to have only limited applications, for instance, as a synthetic substitute for chewing gum.

23. Solvents

Solvents are the hidden element in a broad range of technological activities, including chemical processes, paint, dry cleaning, and metal degreasing. They are used to dissolve organic compounds (water is the usual solvent for inorganic compounds) to enable reactions or polymerization, spreading or ease of use, or to extract compounds from a matrix such as plant material. Dry cleaning is a specialized form of the last group, as it removes fatty substances that adhere dirt to clothing. Many organic compounds either react with or do not dissolve in water, hence the need to find suitable organic chemicals to act as the solvent. It is hard to find compounds that dissolve a wide range of substances, but are also relatively cheap, nonflammable and nontoxic. In practice, the solvents used represent a compromise, often an unsatisfactory one.

The first solvent to be readily available was ethanol (ethyl alcohol) made by fermentation and distillation since the late Middle Ages. Amyl alcohol (fusel oil), a byproduct of ethanol manufacture, also became a popular solvent. Oil of turpentine, made from pine resin, became an important solvent in the eighteenth century and was used in paint and varnishes, and to dissolve rubber. It was also the basis of the earliest form of dry cleaning, which started around 1825. Wood spirit, made by dry distilling wood, first appeared in the early nineteenth century, but its purification into methanol (wood alcohol, methyl alcohol), acetone, and methyl ethyl ketone only took place in the middle of that century. As late as 1914, acetone and methanol were the only significant solvents in the U.S. (by volume), which had access to extensive virgin woodland. Synthetic methanol, made by treating carbon monoxide with hydrogen under pressure, was first made by the German chemical firm BASF in 1923 and eventually replaced the natural product.

24. Synthetic Resins

Chemistry became particularly conspicuous in the twentieth century through synthetic polymers. They include resinous products that are converted into plastics, laminates, surface coatings, and adhesives. Polymers exist because carbon has the property of forming single and multiple bonds with other carbons. In 1922 Hermann Staudinger suggested that polymers were macromolecules. Despite initial opposition, his ideas were accepted from around 1930 and had a considerable impact on industrial developments. The theory and mechanism of the processes whereby small molecules, the monomers, join in repeating units to create giant molecules, the polymers, was established around 1930, following the studies of Wallace Hume Carothers at the DuPont Company in the U.S. He identified two processes, condensation and addition, that distinguish between the main types of products. This provides a useful means for understanding historical developments.

From around 1900, chemists, electrical engineers, and inventors sought out novel products to replace or supplement natural rubber and gutta percha. Most promising was the chemical reaction between phenol and formaldehyde. Leo Hendrik Baekeland, a Belgian who had emigrated to the U.S., carefully controlled the conditions and recognized the catalytic action of acids and bases. He perfected the process in 1907. His main product was a resin readily converted into the first of the thermoplastics, those that set hard and rigid. Baekeland set up the General Bakelite Company in Perth Amboy, New Jersey, in 1910. Another early inventor was Sir James Swinburne, in England, but his process was covered by Baekeland’s patent.

25. Synthetic Rubber

Rubber is a ubiquitous material in modern society, enhancing the quality of life in a myriad of applications. It was unknown in the Western world until the Spanish began their explorations of America, where they found Indian tribes playing games with a ball made from the milky sap obtained by cutting the bark of local trees. In France this sap, or latex, was called caoutchouc after the native name for the ‘‘weeping tree’’ that produced it, while the English called it Indian rubber because it was useful for removing pencil marks from paper. A number of trees and shrubs produced such latex, including the orders Euphorbiaceae, Urticaceae, Apocynaceae, and Asclepiadaceae, but only two natural sources became commercially important (Hevea brasiliensis and Parthenium argentatum).

The use of rubber for practical purposes was slow to develop because the tree latex coagulated quickly and was difficult to process in the solid form. After solvents were discovered that would dissolve the solid rubber, products were made that took advantage of rubber’s elasticity and waterproofing capability, but these crude materials suffered from an inherent stickiness and a form that changed depending on the temperature. With the discovery of the vulcanization process by Charles Goodyear in 1839, the rubber industry had a technique for eliminating these difficulties and better consumer products soon appeared on the market.

After World War II, synthetic rubber plants were built worldwide, and by 1960 the use of synthetic rubber surpassed that of natural rubber for the first time. According to the International Institute of Synthetic Rubber Producers, by the end of 2001, ‘‘The yearly capacity of synthetic rubber manufacturing plants around the globe totals about 12 million metric tons and the capacity of tree-grown natural rubber produced on rubber plantations is approximately 8 million metric tons.’’

History of Chemical Industry and Technology

Although people have made and used chemicals for thousands of years, the modern industry, based on large-scale production, emerged during the Industrial Revolution of the late eighteenth and early nineteenth centuries. The first industrial chemical—sulfuric acid—dates from the mid-eighteenth century when large lead-lined chambers were used to allow the oxidation of sulfur dioxide, made by burning sulfur, to sulfur trioxide, which reacts with water to produce acid. By the mid nineteenth century sulfuric acid plants had grown very large and had reached a high degree of technical sophistication, incorporating most of the techniques of modern chemical engineering. The availability of cheap sulfuric acid allowed the development of cheap alkali by the LeBlanc process, first developed in France but commercialized in Great Britain after 1810. Sulfuric acid was converted to sodium carbonate through a series of reactions with salt, limestone, and charcoal. Large quantities of acids and bases were consumed in Great Britain principally in textile operations, such as washing, bleaching, and dyeing.

Armed with these two reagents—acid and base—chemists began to experiment with a wide variety of substances, many of them organic (carbon-containing). By midcentury chemists had discovered some useful new compounds. In 1856, a young English chemist, William H. Perkin while naively trying to convert coal-tar into the valuable antimalarial quinine produced a purple colored solution instead. At the moment of this discovery extremely expensive purple was the fashionable color among Europe’s elite. Using cheap coal-tar, a waste product from coal gasification plants that supplied illuminating gas to cities, Perkin developed a process to make a purple dye, mauve, by oxidizing aniline (benzene with an ammonia group substituted for a hydrogen atom). Other chemists soon discovered that the larger class of chemicals based on benzene rings would yield a rainbow of colors when reacted with acids and bases. The systematic and highly profitable exploitation of aniline dyes shifted in the 1870s to the new nation of Germany where the government, universities, and emerging chemical companies cooperated to develop this important industry. By World War I, three German companies, Bayer, BASF, and Hoechst controlled about 90 percent of the world’s dyestuffs production. German chemists isolated the chemicals made by the madder and indigo plants that produced red and blue dyes, respectively. Chemists and engineers then learned how to manufacture these chemicals from coal-tar chemicals, replacing natural dyes which were major agricultural products of several countries, especially Turkey (madder) and India (indigo). Dyestuffs chemistry led German chemists into new fields such as pharmaceuticals with the discovery of aspirin by Felix Hoffmann and salvarsan (the first effective treatment for syphilis) by Paul Erlich. Another dyestuffs-related chemical, TNT (trinitrotoluene) would play a critical role as a shell-bursting explosive in World War I.

Explosives were revolutionized by chemists beginning in the middle of the nineteenth century. Experiments with nitric acid and organic molecules resulted in nitrate groups bonding onto the organic molecules, creating highly flammable or even explosive compounds. This characteristic resulted from the molecular proximity of a fuel (the organic compound) and oxygen (there are three oxygen atoms in each nitrate group). The most notorious of these new compounds was nitroglycerin, a liquid with tremendous explosive energy that was so unstable it often detonated prematurely. In Sweden, Alfred Nobel stabilized nitroglycerin by absorbing it into diatomaceous earth to produce a putty-like substance that could be extruded into paper casings. He called his product dynamite, and beginning in the 1870s it displaced black powder in blasting operations. Dynamite was one of the technological advances that would make projects such as the Panama Canal feasible.

Even more important than dynamite was its chemical cousin, nitrocellulose, prepared by reacting nitric acid with cotton fibers. This still cotton-like material became the basis for smokeless powder, which in the 1890s began to replace black powder as the propellant in guns and cannon. Smokeless powder burned much more cleanly than black powder and was much more powerful. The new propellant made the machine guns and heavy artillery into the terribly effective weapons that turned World War I into a bloody stalemate. Smokeless powder had a tendency to decompose causing spontaneous fires and explosions, until German chemists discovered a dyestuffs- related compound that stabilized the powder in 1908. Another key chemical in the munitions machine was TNT, which exploded on shell impact causing huge craters and saturating the air with shrapnel.

The ingenuity of chemists added another horrific element to life in the trenches—poison gas. At the Battle of Ypres in 1915, German chemist Fritz Haber orchestrated the release of 5000 cylinders of chlorine which drifted with the wind into the Allied lines. The burning, choking gas caused panic in the Allied army but the Germans were not prepared to attack and so lost the advantage of its new weapon. Afterward both sides used poison gases such as lewisite, phosgene and mustard gas throughout the remainder of the war. All of these gases contained chlorine, which could be made in large quantities using electrochemical technology.

The development of the dynamo in the 1870s made available large quantities of electricity that could be used to make chemicals, many of which could not be economically made by other methods. Perhaps, the most important example was aluminum, which had semiprecious metal status—a small pyramid of it capped the Washington Monument which was completed in 1883. Three years later, Charles Martin Hall in the U. S. and Paul Louis Toussaint Heroult in France discovered a process to make aluminum using electricity. This method is still used today.

Another important electrochemical process was the production of chlorine and caustic soda (sodium hydroxide) from salt water. Chorine was used principally in bleaching powder and sodium hydroxide became the major base, replacing earlier compounds such as sodium carbonate. This process began to be used in 1890s; several electrolytic plants were built near Niagara Falls where hydroelectric power was available, and Herbert Dow built an early plant in Midland, Michigan where there was a rich supply of brine wells.

Other important materials were made in electric furnaces, which could generate very high temperatures, invented by Henry Moissan in 1892. One new ceramic compound was silicon carbide, which is so hard that it can be used to shape metals by grinding. Another was calcium carbide which reacts with water to produce acetylene, used in early automobile head lights and in oxyacetylene metal-cutting torches. Made from coal, acetylene became an early chemical building block used to make other chemicals.

The development of the Haber–Bosch ammonia process between 1906 and 1912 was a technological and scientific tour de force that became a prototype for future chemical processes. One of the great scientific and technological challenges of the late nineteenth century was ‘‘fixing nitrogen.’’ Nitrogen was an essential ingredient in explosives and fertilizer. Most of the world’s useable nitrogen came from nitrate mines in the Atacama desert in northern Chile. Of course, air is 80 percent nitrogen, but it is almost chemically inert because it consists of two tightly bound atoms. Chemists sought ways to break those bonds. One way to do this was to react nitrogen and hydrogen to make ammonia. On paper it looked simple; in the laboratory it did not happen under normal conditions. A solution to this apparent impasse was suggested by theoretical considerations derived from the evolving disciplines of kinetics (the rate of chemical reactions) and chemical thermodynamics (determines the feasibility of particular reactions). The ammonia reaction was found to be feasible by German chemists Walter Nernst and Fritz Haber. Their calculations showed that the reaction would occur at very high temperatures (for kinetics) and very high pressures (for thermodynamics). The challenge then became technological: was it possible to build steel vessels that could withstand temperatures of 500C and a pressure of 200 atmospheres? After Haber was able to make ammonia in laboratory scale apparatus, Carl Bosch of the BASF Company oversaw the development of a commercial process. Some of the early reactors were made from Krupp cannons. An essential part of the process was the development of a catalyst, a substance that causes the nitrogen and hydrogen to react with each other. At BASF, Alwin Mittasch led an exhaustive search until an efficient and durable iron-based catalyst was developed. The first large plant started up in 1913 a year before World War I would make Chilean nitrates unobtainable in Germany because of Britain’s dominance of the seas. Without ‘‘synthetic’’ nitrogen, the Germans could not have sustained their war effort for four years.

In the 1920s BASF would expand on its high-temperature, high-pressure technological base by developing processes to make methanol from carbon monoxide and hydrogen and gasoline from coal. Before the new process, methanol was obtained by distilling it from wood (hence its name wood alcohol). The synthetic gasoline project was initiated by predictions of impending shortages of crude oil. After 1929, the discovery of the east Texas oil field increases world crude supplies and the Great Depression lowered demand for gasoline, the huge investment in synthetic gasoline technology threatened the viability of the giant IG Farben chemical combine. (The major German chemical companies had merged in 1925 primarily to sustain export markets.) The project and company would be rescued by Hitler after he came to power in 1933, since a domestic supply of gasoline—Germany has no oil—would be essential in a future war.

Hitler’s policy of autarky sustained another project that would have important consequences for the chemical industry—synthetic rubber. Making synthetic versions of natural materials had been a long-standing objective of the chemists and one of the foundations of the chemical industry. Dyestuffs had been the first major success, but chemists also sought to make other substances, especially silk and rubber. Until the 1920s the basic structure of these substances was a matter of scientific uncertainty. This, however, did not stop chemists from forging ahead trying to make synthetic substitutes for exotic and expensive natural materials.

The origin of synthetic materials dates to 1870 when Albany tinkerer, John Wesley Hyatt formed a solid plastic from a mixture of nitrocellulose and camphor, which he called celluloid. According to tradition, Hyatt was looking for a substitute for expensive elephant ivory in billiard balls. When his new material failed in this use, he then made celluloid look like exotic materials—ivory, amber, and tortoiseshell—so it would be used in toilet sets, toys, and numerous other trinket-like applications. Its most enduring legacy was as the film base that made motion pictures possible beginning in the 1890s. An unsuccessful use of nitrocellulose was as an artificial silk fiber that, among other deficiencies, was highly flammable.

A much better silk-like fiber was rayon, formed by dissolving cellulose to make a syrupy viscose solution that was extruded through small holes in a plate into another chemical bath that solidified the fiber. Charles Cross and Edward Bevan in Britain discovered this process in the 1890s, while attempting to make improved light bulb filaments. After 1910 the market for rayon fibers began to expand rapidly worldwide; the fashion industry embraced it the 1920s; and during the Great Depression it replaced silk in all apparel except stockings. Rayon was the biggest new product for the chemical industry in the interwar years.

Rayon was just one a growing number of products made of large molecules (or macromolecules), in this case it was natural cellulose. Chemists were beginning to make entirely new large molecules. A pioneer is this effort was Leo Baekeland who invented a hard plastic he dubbed Bakelite in 1907. The new material was made by heating phenol and formaldehyde under pressure. Among the many uses for Bakelite was as a substitute for ivory in billiard balls.

The growing importance of and interest in large molecules in the 1920s sparked a scientific debate, especially in Germany—still the center of chemistry— about their structure. Although many chemists argued that large molecules were held together by peculiar forces, Hermann Staudinger put forth the hypothesis that large organic molecules were just that—larger versions of common organic chemicals held together by same types of chemical bonds. Following Staudinger, Wallace H. Carothers, a researcher in the DuPont Company developed methods for making large molecules, or polymers, in the laboratory. Out of this research DuPont researchers discovered neoprene synthetic rubber (1930) and nylon (1934). By 1940 neoprene had established itself as a specialty rubber and nylon had become the preferred stocking fiber. Once the mysteries surrounding polymers had been solved, chemists everywhere began to explore this large and promising new field.

Perhaps the most significant discovery, both historically and for the future chemical industry, was made in 1929 by IG Farben chemists who made a general purpose synthetic rubber from a polymer consisting of repeating units of butadiene and styrene. At the time of this breakthrough virtually all of the world’s rubber came from British controlled plantations in Malaysia. By early 1942, these were all in Japanese occupied territory. The first year of American fighting was hampered by a lack of rubber which threatened to bring the effort to a thudding halt. To resolve this crisis the U.S. government organized a cooperative venture between oil, chemical, and tire companies to rapidly build up an American synthetic rubber capability. This initiative was a marked success, production went from nothing to 800,000 tons in two years. One of the major obstacles that had to be overcome was to develop processes to make enormous quantities of styrene and butadiene. Styrene was available before the war in limited quantities but butadiene was not a commercial chemical. The supply of butadiene came primarily from oil companies, which had previously concentrated on making fuels not chemicals.

In the interwar years a few companies such as Union Carbide and Shell Oil had begun to make chemicals from petroleum and natural gas. One notable product introduced in the 1930s was ethylene glycol—automobile radiator coolant antifreeze. Until World War II organic chemicals used as feedstocks for the chemical industry were distilled from coal. For example, the type of nylon DuPont commercialized was determined mainly by the abundance of benzene, a major coal impurity. After World War II the oil and chemical industries, especially in the U.S., would soon shift to petrochemical feedstocks.

The oil industry was now generating large quantities of chemicals as a byproduct of new processes developed to produce more gasoline from a barrel of crude of oil and to produce higher octane fuels, especially necessary for aviation gasoline during World War II. Crude oil is a complex mixture of hydrocarbons with varying carbon atom chain lengths. Originally, natural gasoline, which contains five to nine carbons in each molecule was distilled out of crude oil. In 1913, E. M. Burton developed a cracking process in which he subjected the heavier fractions of crude oil to heat and pressure which broke the larger molecules into smaller ones, some of which were in the gasoline-size range. In the 1930s, French inventor and engineer, Eugene Houdry, added a catalyst to this process which significantly improved its overall performance. A decade later, an improved catalytic process called fluidized bed cracking was developed by Massachusetts Institute of Technology chemical engineers and Standard Oil of New Jersey. This process has been used ever since. Also during the late 1930s oil companies began to develop processes to combine some of the smaller cracked molecules into larger ones that could boost the octane rating of gasoline. During World War II, American 100-octane aviation fuel helped Allied pilots win the air war over Europe.

A few years after the war ended, the Universal Oil Products company, a research organization, introduced a new process which had been developed by Vladimir Haensel. Called ‘‘platforming’’ because of its platinum catalyst, it dramatically improved the octane rating of gasoline primarily by stripping hydrogen atoms from cyclical compounds, converting them to benzene, tolulene, and xylene. These compounds were not only important for high-octane gasoline but were in great demand by the chemical industry as raw materials, especially for the booming plastics and polymers businesses.

The dramatic post-World War II expansion of the chemical industry was led by plastics and polymers. Shortages of metals and other materials during the war had prompted the U.S. government to encourage manufacturers to use plastics for a wide variety of applications. For example, vinyl resin (mostly polyvinyl chloride or PVC) production increased from 2.3 million to 100 million kilograms. Although many plastics ended up in applications such as army bugles, others served essential high-technology functions. Polyethylene, a difficult to make plastic, had unique insulating properties needed for radar. DuPont’s exotic polymer Teflon, which did not melt, dissolve in solvents, or stick to anything, was used as a sealant in the Manhattan Project for the atomic bomb. Clear acrylic plastic became the material for airplane windows and bomber gunner turrets.

After the war both the uses and varieties of polymers increased to fulfill the demand by consumers for whom convenience became a hallmark of modern life. A New England inventor, Earl Tupper, introduced his line of polyethylene food storage containers—Tupperware—that preserved leftovers and kept them neatly in the refrigerator. The most sensational new products were synthetic textile fibers that made clothing more affordable, machine washable, drip dry, and wrinkle free. DuPont’s nylon took over the stocking market and made major inroads in other apparel. Polyester, discovered by two British chemists in 1940, was used instead of wool in suits and blended with cotton to make permanent press garments. Acrylic fibers made sweaters, especially lightweight ones, popular with postwar women. By 1956, synthetic fibers had eclipsed wool as the number two textile fiber consumed in the U.S. By 1970, synthetic fiber consumption surpassed that of cotton in apparel.

At the same time that synthetic fibers were revolutionizing modern wardrobes, new types of plastics found myriad uses. The major breakthrough in plastics was made when German chemist, Karl Ziegler in 1953 discovered a new type of catalyst that produced new kinds of polymers, notably linear polyethylene and polypropylene. These two plastics had outstanding properties such as toughness which led to many uses, especially food packaging. As polymer science matured in the 1950s, chemists made more complex and sophisticated compounds, examples being DuPont’s Kevlar polyaramid and Lycra spandex fibers.

Another significant growth sector for the post- World War II chemical industry was organic-chemical based pesticides. The archetype was DDT, whose remarkable kill-on-contact property was discovered by Paul Mueller in Switzerland in 1939. Most earlier insecticides were poisons, such as lead arsenate, that had to be ingested. During the war, George W. Merck, working on biological warfare for the government, discovered that a DuPont plant growth compound called 2,4-D was actually an effective herbicide. After the war chemical companies focused research efforts on finding new insecticides, herbicides, and fungicides. Although Rachel Carson’s Silent Spring (1962) publicized the toxic effects of DDT on birds and raised questions about the effect of pesticides on human health, during that decade 96 new insecticides, 110 new herbicides, and 50 new fungicides were introduced. Insecticides included organophosphorus compounds, carbamates, and synthetic pyrethrins. DuPont in 1967 introduced Benlate (benomyl), the first fungicide that was taken up internally rather than being effective only on the leaf surfaces. In the 1970s Monsanto introduced its blockbuster herbicide, Roundup (glyphosate), which was suitable for a wide variety of crops. In the 1990s chemical companies, especially Monsanto and DuPont combined biotechnology and herbicides to create crop seeds that were compatible with specific herbicides, and to incorporate insecticidal properties into plants by splicing in genes from other organisms. These so-called genetically modified foods have created controversy in Europe but have met with little resistance in the U.S.

It became evident in the 1960s that the chemical industry was maturing. During the 1970s the industry was beleaguered by spikes in the cost of energy and feedstocks, and environmental legislation that required major capital investments in pollution control and abatement. By the 1980s, the chemical industry had become very competitive worldwide with growth and profits tightly linked to larger business cycles. Since then the industry had undergone massive reorganization in response to these new economic realities. For the most part, chemicals, if not the companies that make them, have become commodities. Because it still has significant research capabilities, the chemical industry is hoping that new technologies such as nanotechnology—very small molecular structures— or green chemistry—replacing petroleum with renewable feedstocks—might restore chemicals to the essential status it enjoyed in the twentieth century.

ORDER HIGH QUALITY CUSTOM PAPER

An official website of the United States government

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

• Publications
• Account settings

Preview improvements coming to the PMC website in October 2024. Learn More or Try it out now .

• Advanced Search
• Journal List
• Front Microbiol
• PMC10168541

A review on nanoparticles: characteristics, synthesis, applications, and challenges

The significance of nanoparticles (NPs) in technological advancements is due to their adaptable characteristics and enhanced performance over their parent material. They are frequently synthesized by reducing metal ions into uncharged nanoparticles using hazardous reducing agents. However, there have been several initiatives in recent years to create green technology that uses natural resources instead of dangerous chemicals to produce nanoparticles. In green synthesis, biological methods are used for the synthesis of NPs because biological methods are eco-friendly, clean, safe, cost-effective, uncomplicated, and highly productive. Numerous biological organisms, such as bacteria, actinomycetes, fungi, algae, yeast, and plants, are used for the green synthesis of NPs. Additionally, this paper will discuss nanoparticles, including their types, traits, synthesis methods, applications, and prospects.

1. Introduction

Nanotechnology evolved as the achievement of science in the 21st century. The synthesis, management, and application of those materials with a size smaller than 100 nm fall under the interdisciplinary umbrella of this field. Nanoparticles have significant applications in different sectors such as the environment, agriculture, food, biotechnology, biomedical, medicines, etc. like; for treatment of waste water ( Zahra et al., 2020 ), environment monitoring ( Rassaei et al., 2011 ), as a functional food additives ( Chen et al., 2023 ), and as a antimicrobial agents ( Islam et al., 2022 ). Cutting-edge properties of NPs such as; nature, biocompatibility, anti-inflammatory and antibacterial activity, effective drug delivery, bioactivity, bioavailability, tumor targeting, and bio-absorption have led to a growth in the biotechnological, and applied microbiological applications of NPs.

A particle of matter with a diameter of one to one hundred nanometers (nm) is commonly referred to as a nanoparticle or ultrafine particle. Nanoparticles frequently exhibit distinctive size-dependent features, mostly due to their tiny size and colossal surface area. The periodic boundary conditions of the crystalline particle are destroyed when the size of a particle approaches the nano-scale with the characteristic length scale close to or smaller than the de Broglie wavelength or the wavelength of light ( Guo et al., 2013 ). Because of this, many of the physical characteristics of nanoparticles differ significantly from those of bulk materials, leading to a wide range of their novel uses ( Hasan, 2015 ).

2. Emergence of nanotechnology

Nanotechnology emerged in the 1980s due to the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985 ( Bayda et al., 2019 ), with the elucidation. The popularization of a conceptual framework for nanotechnology goals began with the publication of the book Engines of Creation in 1986 ( Bayda et al., 2019 ).

2.1. Early stage of NPs

Carbon nanotubes have been discovered in pottery from Keeladi, India, dating from around 600–300 BC ( Bayda et al., 2019 ; Kokarneswaran et al., 2020 ). Cementite nanowires have been discovered in Damascus steel, a material that dates back to around 900 AD; nevertheless, its origin and creation method are unclear ( Kokarneswaran et al., 2020 ). However, it is unknown how they developed or whether the material containing them was used on purpose.

2.2. Discovery of C, Ag, Zn, Cu, and Au nanoparticles

Carbon NPs were found in 1991, and Iijima and Ichihashi announced the single-wall carbon nanotube synthesis with a diameter of 1 nanometer in 1993 ( Chen et al., 2021 ). Carbon nanotubes (CNTs), also known as Bucky tubes, are a kind of nanomaterial made up of a two-dimensional hexagonal lattice of carbon atoms. They are bent one way and joined to produce a hollow cylindrical cylinder. Carbon nanotubes are carbon allotropes that fall between Fullerene (0 dimensional) and Grapheme (2 dimensional) ( Chen et al., 2021 ).

In addition, M. C. Lea reported that the synthesis of citrate-stabilized silver colloid almost 120 years ago ( Nowack et al., 2011 ). This process produces particles with an average diameter of 7 to 9 nm. Nanoscale size and citrate stabilization are analogous to recent findings on nanosilver production employing silver nitrate and citrate ( Majeed Khan et al., 2011 ). The use of proteins to stabilize nanosilver has also been documented as early as 1902 ( Nowack et al., 2011 ; Beyene et al., 2017 ). Since 1897, a nanosilver known as “Collargol” has been made commercially and used for medicinal purposes ( Nowack et al., 2011 ). Collargol, a type of silver nanoparticle, has a particle size of about 10 nanometers (nm). This was determined as early as 1907, and it was found that the diameter of Collargol falls within the nanoscale range. In 1953, Moudry developed a different type of silver nanoparticle called gelatin-stabilized silver nanoparticles, with a diameter ranging from 2–20 nm. These nanoparticles were produced using another method than Collargol. The necessity of nanoscale silver was recognized by the creators of nanosilver formulations decades ago, as seen by the following remark from a patent: “for optimal efficiency, the silver must be disseminated as particles of colloidal size less than 25 nm in crystallite size”( Nowack et al., 2011 ).

Gold NPs (AuNPs) have a long history in chemistry, going back to the Roman era when they were used to decorate glassware by staining them. With the work of Michael Faraday, who may have been the first to notice that colloidal gold solutions have characteristics different from bulk gold, the contemporary age of AuNP synthesis began more than 170 years ago. Michael Faraday investigated the making and factors of colloidal suspensions of “Ruby” gold in 1857. They are among the magnetic nanoparticles due to their distinctive optical and electrical characteristics. Under specific illumination circumstances, Faraday showed how gold nanoparticles might create solutions of various colors ( Bayda et al., 2019 ; Giljohann et al., 2020 ).

3. Classification of NPs

Nanoparticles (NPs) are categorized into the following classes based on their shape, size, and chemical characteristics;

3.1. Carbon-based NPs

Fullerenes and carbon nanotubes (CNTs) are the two essential sub-categories of carbon-based NPs. NPs of globular hollow cages, like allotropic forms of carbon, are found in fullerenes. Due to their electrical conductivity, high strength, structure, electron affinity, and adaptability, they have sparked significant economic interest. These materials have organized pentagonal and hexagonal carbon units, each of which is sp2 hybridized. While CNTs are elongated and form 1–2 nm diameter tubular structures. These fundamentally resemble graphite sheets rolling on top of one another. Accordingly, they are referred to as single-walled (SWNTs), double-walled (DWNTs), or multi-walled carbon nanotubes (MWNTs) depending on how many walls are present in the rolled sheets ( Elliott et al., 2013 ; Astefanei et al., 2015 ).

3.2. Metal NPs

Metal NPs are purely made of metals. These NPs have distinctive electrical properties due to well-known localized surface Plasmon resonance (LSPR) features. Cu, Ag, and Au nanoparticles exhibit a broad absorption band in the visible region of the solar electromagnetic spectrum. Metal NPs are used in several scientific fields because of their enhanced features like facet, size, and shape-controlled synthesis of metal NPs ( Khan et al., 2019 ).

3.3. Ceramics NPs

Ceramic NPs are tiny particles made up of inorganic, non-metallic materials that are heat-treated and cooled in a specific way to give particular properties. They can come in various shapes, including amorphous, polycrystalline, dense, porous, and hollow, and they are known for heat resistance and durable properties. Ceramic NPs are used in various applications, including coating, catalysts, and batteries ( Sigmund et al., 2006 ).

3.4. Lipid-based NPs

These NPs are helpful in several biological applications because they include lipid moieties. Lipid NPs typically have a diameter of 10–1,000 nm and are spherical. Lipid NPs, i.e., polymeric NPs, have a solid lipid core and a matrix consisting of soluble lipophilic molecules ( Khan et al., 2019 ).

3.5. Semiconductor NPs

Semiconductor NPs have qualities similar to metals and non-metals. That is why Semiconductor NPs have unique physical and chemical properties that make them useful for various applications. For example, semiconductor NPs can absorb and emit light and can be used to make more efficient solar cells or brighter light-emitting diodes (LEDs). They can make smaller and faster electronic devices, such as transistors, and can be used in bio imaging and cancer therapy ( Biju et al., 2008 ).

3.6. Polymeric NPs

Polymeric NPs with a size between 1 and 1,000 nm can have active substances surface-adsorbed onto the polymeric core or entrapped inside the polymeric body. These NPs are often organic, and the term polymer nanoparticle (PNP) is commonly used in the literature to refer to them. They resemble Nano spheres or Nano capsules for the most part ( Khan et al., 2019 ; Zielińska et al., 2020 ).

4. Types of different metal-based NPs

Metal NPs are purely made of metal precursors. Due to well-known localized surface plasmon resonance (LSPR) characteristics, these NPs possess unique optoelectrical properties. NPs of the alkali and noble metals, i.e., Cu, Ag, and Au, have a broad absorption band in the visible zone of the solar electromagnetic spectrum. The facet, size, and shape-controlled synthesis of metal NPs are essential in present-day cutting-edge materials ( Dreaden et al., 2012 ; Khan et al., 2019 ).

4.1. Silver nanoparticles (AgNPs)

AgNPs are particles with a size range of 1–100 nanometers made of silver. They have unique physical and chemical properties due to their small size, high surface area-to-volume ratio, and ability to absorb and scatter light in the visible and near-infrared range. Because of their relatively small size and high surface-to-volume ratios, which cause chemical and physical differences in their properties compared to their bulk counterparts, silver nanoparticles may exhibit additional antimicrobial capabilities not exerted by ionic silver ( Shenashen et al., 2014 ).

Besides, AgNPs can be created in various sizes and forms depending on the manufacturing process, the most common of which is chemical reduction. The AgNPs were created by chemically reducing a 12 mM AgNO3 aqueous solution. The reaction was carried out in an argon environment using 70 mL of this solution containing PVP (keeping the molar ratio of the repeating unit of PVP and Ag equal to 34) and 21 mL of Aloe Vera. The mixture was agitated in ultrasonic for 45 min at ambient temperature, then heated 2°C/min to 80°C and left for 2 h to generate a transparent solution with tiny suspended particles that must be removed by simple filtering ( Shenashen et al., 2014 ; Gloria et al., 2017 ).

4.2. Zinc nanoparticles (ZnONPs)

Zinc nanoparticles (ZnONPs) are particles with a size range of 1–100 nm made of zinc. Zinc oxide (ZnO) NPs are a wide band gap semiconductor with a room temperature energy gap of 3.37 eV. Its catalytic, electrical, optoelectronic, and photochemical capabilities have made it widely worthwhile ( Kumar S.S. et al., 2013 ). ZnO nanostructures are ideal for catalytic reaction processes ( Chen and Tang, 2007 ). Laser ablation, hydrothermal methods, electrochemical depositions, sol-gel method, chemical vapor deposition, thermal decomposition, combustion methods, ultrasound, microwave-assisted combustion method, two-step mechanochemical-thermal synthesis, anodization, co-precipitation, electrophoretic deposition, and precipitation processes are some methods for producing ZnO nanoparticles ( Madathil et al., 2007 ; Moghaddam et al., 2009 ; Ghorbani et al., 2015 ).

4.3. Copper nanoparticles (CuNPs)

Copper nanoparticles (CuNPs) comprise a size range of 1–100 nm of copper-based particles ( Khan et al., 2019 ). Cu and Au metal fluorescence have long been known to exist. For excitation at 488 nm, a fluorescence peak centering on the metals’ interband absorption edge has been noted. Additionally, it was noted that the fluorescence peaked at the same energy at two distinct excitation wavelengths (457.9–514.5 and 300–400 nm), and the high-energy tail somewhat grows with increased photon energy pumping. A unique, physical, top-down EEW approach has been used to create Cu nanoparticles. The EEW method involves sending a current of *1,010 A/m2 (1,010 A/m2) across a thin Cu wire, which explodes on a Cu plate for a duration of 10–6 s ( Siwach and Sen, 2008 ).

4.4. Gold nanoparticles (AuNPs)

Gold nanoparticles(AuNPs) are nanometers made of gold. They have unique physical and chemical properties and can absorb and scatter light in the visible and near-infrared range ( Rad et al., 2011 ; Compostella et al., 2017 ).

Scientists around the turn of the 20th century discovered anisotropic AuNPs. Zsigmond ( Li et al., 2014 ) said that gold particles “are not always spherical when their size is 40 nm or lower” in his book, released in 1909. Additionally, he found anisotropic gold particles of various colors. Zsigmondy won the Nobel Prize in 1925 for “his demonstration of the heterogeneous character of colloidal solutions and the methods he utilized” and for developing the ultramicroscope, which allowed him to see the forms of Au particles. He noticed that gold frequently crystallized into a six-sided leaf shape ( Li et al., 2014 ).

AuNPs are the topic of extensive investigation due to their optical, electrical, and molecular-recognition capabilities, with numerous prospective or promised uses in a wide range of fields, including electron microscopy, electronics, nanotechnology, materials science, and biomedicine ( Rad et al., 2011 ).

4.5. Aluminum nanoparticles (AlNPs)

Aluminum nanoparticles (AlNPs) are nanoparticles made of aluminum. Aluminum nanoparticles’ strong reactivity makes them promising for application in high-energy compositions, hydrogen generation in water processes, and the synthesis of alumina 2D and 3D structures ( Lerner et al., 2016 ).

4.6. Iron nanoparticles (FeNPs)

Iron nanoparticles(FeNPs) are particles with a size range of 1−100 nanometers ( Khan et al., 2019 ) made of iron. FeNPs have several potential applications, including their use as catalysts, drug delivery systems, sensors, and energy storage and conversion. They have also been investigated for use in photovoltaic and solar cells and water purification and environmental remediation. FeNPs can also be used in magnetic resonance imaging (MRI) as contrast agents to improve the visibility of tissues and organs. They can also be used in magnetic recording media, such as hard disk drives ( Zhuang and Gentry, 2011 ; Jamkhande et al., 2019 ).

As with any NPs, there are potential health and safety concerns associated with using FeNPs, e.g., FeNPs are used to deliver drugs to specific locations within the body, such as cancer cells and used in MRI, and used to remove contaminants from water ( Farrell et al., 2003 ; Zhuang and Gentry, 2011 ). Tables 1 , ​ ,2 2 show the characteristics of metal-based nanoparticles and the techniques to study their characteristics, respectively.

Characteristics of metal based nanoparticles.

Different analytical techniques and their purposes in studying nanoparticles.

5. Approaches for the synthesis of metal NPs

There are mainly three types of approaches for the synthesis of NPs: the physical, chemical, and biological approaches. The physical approach is also called the top-down approach, while chemical and biological approaches are collectively called the bottom-up approach. The biological approach is also named green systems of NPs. All these approaches are further sub-categorized into various types based upon their method adopted. Figure 1 illustrates each approach’s reported methods for synthesizing NPs.

Approaches of NPs synthesis.

5.1. Top down/physical approach

Bulk materials are fragmented in top-down methods to create nano-structured materials ( Figure 2 ). They are additionally known as physical approaches ( Baig et al., 2021 ). The following techniques can achieve a top-down approach;

Difference between top-down and bottom-up approaches.

5.1.1. Mechanical milling

The mechanical milling process uses balls inside containers and may be carried out in various mills, typically planetary and shaker mills, which is an impact process with high energy ( Gorrasi and Sorrentino, 2015 ). Mechanical milling is a practical approach for creating materials at the nanoscale from bulk materials. Aluminum alloys that have been strengthened by oxide and carbide, spray coatings that are resistant to wear, nanoalloys based on aluminum, nickel, magnesium, and copper, and a variety of other nanocomposite materials may all be created mechanically. A unique class of nanoparticles known as ball-milled carbon nanomaterials has the potential to meet the needs for energy storage, energy conversion, and environmental remediation ( Yadav et al., 2012 ; Lyu et al., 2017 ).

5.1.2. Electrospinning

Typically, it is used to create nanofibers from various materials, most often polymers ( Ostermann et al., 2011 ). A technique for creating fibers called electrospinning draws charged threads from polymer melts or solutions up to fiber sizes of a few hundred nanometers ( Chronakis, 2010 ). Coaxial electrospinning was a significant advancement in the field of electrospinning. The spinneret in coaxial electrospinning is made up of two coaxial capillaries. Core-shell nanoarchitectures may be created in these capillaries using two viscous liquids, a viscous liquid as the shell and a non-viscous liquid as the core ( Du et al., 2012 ). Core-shell and hollow polymer, inorganic, organic, and hybrid materials have all been developed using this technique ( Kumar R. et al., 2013 ).

5.1.3. Laser ablation

A microfeature can be made by employing a laser beam to vaporize a single material ( Tran and Wen, 2014 ). Laser ablation synthesis produces nanoparticles by striking the target material with an intense laser beam. Due to the high intensity of the laser irradiation used in the laser ablation process, the source material or precursor vaporizes, causing the production of nanoparticles ( Amendola and Meneghetti, 2009 ). Laser ablation is an environmentally friendly for producing noble metal nanoparticles ( Baig et al., 2021 ). This method may be used to create a wide variety of nanomaterials, including metal nanoparticles, carbon nanomaterials, oxide composites, and ceramics ( Su and Chang, 2018 ; Baig et al., 2021 ).

5.1.4. Sputtering

Microparticles of a solid material are expelled off its surface during the phenomenon known as sputtering, which occurs when the solid substance is assaulted by intense plasma or gas particles ( Behrisch, 1981 ). According to the incident gaseous ion energy, energetic gaseous ions used in the sputtering deposition process physically expel tiny atom clusters off the target surface ( Muñoz-García et al., 2009 ). The sputtering method is intriguing because it is more affordable than electron-beam lithography, and the composition of the sputtered nanomaterials is similar to the target material with fewer contaminants ( Baig et al., 2021 ).

5.1.5. Electron explosion

In this technique, a thin metal wire is subjected to a high current pulse that causes an explosion, evaporation, and ionization. The metal becomes vaporized and ionized, expands, and cools by reacting with the nearby gas or liquid medium. The condensed vapor finally forms the nanoparticles ( Joh et al., 2013 ). Electron explosion method because it produces plasma from the electrical explosion of a metallic wire, which may produce nanoparticles from a Pt solution without using a reducing agent ( Joh et al., 2013 ).

5.1.6. Sonication

The most crucial step in the creation of nanofluids is sonication. After the mixture has been magnetically stirred in a magnetic stirrer, sonication is performed in an ultrasonication path, ultrasonic vibrator, and mechanical homogenizer. Sonicators have become the industry standard for Probe sonication and are noticeably more powerful and effective when compared to ultrasonic cleaner baths for nanoparticle applications. Probe sonication is highly effective for processing nanomaterials (carbon nanotubes, graphene, inks, metal oxides, etc.) ( Zheng et al., 2010 ).

5.1.7. Pulsed wire discharge method

This is the most used method for creating metal nanoparticles. A pulsating current causes a metal wire to evaporate, producing a vapor that is subsequently cooled by an ambient gas to form nanoparticles. This plan may quickly produce large amounts of energy ( Patil et al., 2021 ).

5.1.8. Arc discharge method

Two graphite rods are adjusted in a chamber with a constant helium pressure during the Arc Discharge procedure. It is crucial to fill the chamber with helium because oxygen or moisture prevents the synthesis of fullerenes. Arc discharge between the ends of the graphite rods drives the vaporization of carbon rods. Achieving new types of nanoparticles depends significantly on the circumstances in which arc discharge occurs. The creation of several nanostructured materials may be accomplished with this technique ( Berkmans et al., 2014 ). It is well-recognized for creating carbon-based materials such as fullerenes, carbon nanohorns (CNHs), carbon nanotubes ( Shi et al., 2000 ), few-layer graphene, and amorphous spherical carbon nanoparticles ( Kumar R. et al., 2013 ).

5.1.9. Lithography

Lithography typically uses a concentrated beam of light or electrons to create nanoparticles, a helpful technique ( Pimpin and Srituravanich, 2012 ). Masked and maskless lithography are the two primary categories of lithography. Without a mask, arbitrary nano-pattern printing is accomplished in maskless lithography. Additionally, it is affordable and easy to apply ( Brady et al., 2019 ).

5.2. Bottom-up approach

Tiny atoms and molecules are combined in bottom-up methods to create nano-structured particles ( Figure 2 ; Baig et al., 2021 ). These include chemical and biological approaches:

5.2.1. Chemical vapor deposition (CVD)

Through a chemical process involving vapor-phase precursors, a thin coating is created on the substrate surface during CVD ( Dikusar et al., 2009 ). Precursors are deemed appropriate for CVD if they exhibit sufficient volatility, high chemical purity, strong evaporation stability, cheap cost, a non-hazardous nature, and long shelf life. Additionally, its breakdown should not leave behind any contaminants. Vapor phase epitaxy, metal-organic CVD, atomic layer epitaxy, and plasma-enhanced CVD are only a few CVD variations. This method’s benefits include producing very pure nanoparticles that are stiff, homogeneous, and strong ( Ago, 2015 ). CVD is an excellent approach to creating high-quality nanomaterials ( Machac et al., 2020 ). It is also well-known for creating two-dimensional nanoparticles ( Baig et al., 2021 ).

5.2.2. Sol-gel process

A wet-chemical approach, called the sol-gel method, is widely utilized to create nanomaterials ( Das and Srivasatava, 2016 ; Baig et al., 2021 ). Metal alkoxides or metal precursors in solution are condensed, hydrolyzed, and thermally decomposed. The result is a stable solution or sol. The gel gains greater viscosity as a result of hydrolysis or condensation. The particle size may be seen by adjusting the precursor concentration, temperature, and pH levels. It may take a few days for the solvent to be removed, for Ostwald ripening to occur, and for the phase to change during the mature stage, which is necessary to enable the growth of solid mass. To create nanoparticles, the unstable chemical ingredients are separated. The generated material is environmentally friendly and has many additional benefits thanks to the sol-gel technique ( Patil et al., 2021 ). The uniform quality of the material generated, the low processing temperature, and the method’s ease in producing composites and complicated nanostructures are just a few of the sol-gel technique’s many advantages ( Parashar et al., 2020 ).

5.2.3. Co-precipitation

It is a solvent displacement technique and is a wet chemical procedure. Ethanol, acetone, hexane, and non-solvent polymers are examples of solvents. Polymer phases can be either synthetic or natural. By mixing the polymer solution, fast diffusion of the polymer-solvent into the non-solvent phase of the polymer results. Interfacial stress at two phases results in the formation of nanoparticles ( Das and Srivasatava, 2016 ). This method’s natural ability to produce high quantities of water-soluble nanoparticles through a straightforward process is one of its key benefits. This process is used to create many commercial iron oxide NP-based MRI contrast agents, including Feridex, Reservist, and Combidex ( Baig et al., 2021 ; Patil et al., 2021 ).

5.2.4. Inert gas condensation/molecular condensation

Metal NPs are produced using this method in large quantities. Making fine NPs using the inactive gas compression approach has been widespread, which creates NPs by causing a metallic source to disappear in an inert gas. At an attainable temperature, metals evaporate at a tolerable pace. Copper metal nanoparticles are created by vaporizing copper metal inside a container containing argon, helium, or neon. The atom quickly loses its energy by cooling the vaporized atom with an inert gas after it boils out. Liquid nitrogen is used to cool the gases, forming nanoparticles in the range of 2–100 nm ( Pérez-Tijerina et al., 2008 ; Patil et al., 2021 ).

5.2.5. Hydrothermal

In this method, for the production of nanoparticles, hydrothermal synthesis uses a wide temperature range from ambient temperature to extremely high temperatures. Comparing this strategy to physical and biological ones offers several benefits. At higher temperature ranges, the nanomaterials produced by hydrothermal synthesis could become unstable ( Banerjee et al., 2008 ; Patil et al., 2021 ).

5.2.6. Green/biological synthesis

The synthesis of diverse metal nanoparticles utilizing bioactive agents, including plant materials, microbes, and various biowastes like vegetable waste, fruit peel waste, eggshell, agricultural waste, algae, and so on, is known as “green” or “biological” nanoparticle synthesis ( Kumari et al., 2021 ). Developing dependable, sustainable green synthesis technologies is necessary to prevent the formation of undesirable or dangerous byproducts ( Figure 3 ). The green synthesis of nanoparticles also has several advantages, including being straightforward, affordable, producing NPs with high stability, requiring little time, producing non-toxic byproducts, and being readily scaled up for large-scale synthesis ( Malhotra and Alghuthaymi, 2022 ).

Schematic diagram for biosynthesis of NPs.

5.2.6.1. Biological synthesis using microorganisms

Microbes use metal capture, enzymatic reduction, and capping to create nanoparticles. Before being converted to nanoparticles by enzymes, metal ions are initially trapped on the surface or interior of microbial cells ( Ghosh et al., 2021 ). Use of microorganisms (especially marine microbes) for synthesis of metalic NPs is environmental friendly, fast and economical ( Patil and Kim, 2018 ). Several microorganisms are used in the synthesis of metal NPs, including:

Biosynthesis of NPs by bacteria: A possible biofactory for producing gold, silver, and cadmium sulfide nanoparticles is thought to be bacterial cells. It is known that bacteria may produce inorganic compounds either inside or outside of their cells ( Hulkoti and Taranath, 2014 ). Desulforibrio caledoiensis ( Qi et al., 2013 ), Enterococcu s sp. ( Rajeshkumar et al., 2014 ), Escherichia coli VM1 ( Maharani et al., 2016 ), and Ochrobactrum anhtropi ( Thomas et al., 2014 ) based metal NPs are reported previously for their potential photocatalytic properties ( Qi et al., 2013 ), antimicrobial activity ( Rajeshkumar et al., 2014 ), and anticancer activity ( Maharani et al., 2016 ).

Extracellular synthesis of NPs by bacteria: The microorganisms’ extracellular reductase enzymes shrink the silver ions to the nanoscale range. According to protein analysis of microorganisms, the NADH-dependent reductase enzyme carries out the bio-reduction of silver ions to AgNPs. The electrons for the reductase enzyme come from NADH, which is subsequently converted to NAD+. The enzyme is also oxidized simultaneously when silver ions are reduced to nanosilver. It has been noted that bio-reduction can occasionally be caused by nitrate-dependent reductase. The decline occurs within a few minutes in the quick extracellular creation of nanoparticles ( Mathew et al., 2010 ). At pH 7, the bacterium R. capsulata produced gold nanoparticles with sizes ranging from 10−20 nm. Numerous nanoplates and spherical gold nanoparticles were produced when the pH was changed to four ( Sriram et al., 2012 ). By adjusting the pH, the gold nanoparticles’ form may be changed. Gold nanoparticle shape was controlled by regulating the proton content at various pH levels. The bacteria R. capsulata ’s release cofactor NADH and NADH-dependent enzymes may cause the bioreduction of Au (3+) to Au (0) and the generation of gold nanoparticles. By using NADH-dependent reductase as an electron carrier, it is possible to start the reduction of gold ions ( Sriram et al., 2012 ).

Intracellular synthesis of NPs by bacteria: Three processes are involved in the intracellular creation of NPs: trapping, bioreduction, and capping. The cell walls of microorganisms and ions charge contribute significantly to creating NPs in the intracellular route. This entails specific ion transit in the presence of enzymes, coenzymes, and other molecules in the microbial cell. Microbes have a range of polysaccharides and proteins in their cell walls, which function as active sites for the binding of metal ions ( Slavin et al., 2017 ). Not all bacteria can produce metal and metal oxide nanoparticles. The only ions that pose a significant hazard to microorganisms are heavy metal ions, which, in response to a threat, cause the germs to react by grabbing or trapping the ions on the cell wall via electrostatic interactions. This occurs because a metal ion is drawn to the cell wall’s carboxylate groups, including cysteine and polypeptides, and certain enzymes with a negative charge ( Zhang et al., 2011 ).

Additionally, the electron transfers from NADH via NADH-dependent educates, which serves as an electron carrier and is located inside the plasma membrane, causing the trapped ions to be reduced into the elemental atom. The nuclei eventually develop into NPs and build up in the cytoplasm or the pre-plasmic space. On the other hand, the stability of NPs is provided by proteins, peptides, and amino acids found inside cells, including cysteine, tyrosine, and tryptophan ( Mohd Yusof et al., 2019 ).

Biosynthesis of NPs by fungi: Because monodisperse nanoparticles with distinct dimensions, various chemical compositions, and sizes may be produced, the biosynthesis of nanoparticles utilizing fungus is frequently employed. Due to the existence of several enzymes in their cells and the ease of handling, fungi are thought to be great candidates for producing metal and metal sulfide nanoparticles ( Mohanpuria et al., 2008 ).

The nanoparticles were created on the surface of the mycelia. After analyzing the results and noting the solution, it was determined that the Ag + ions are initially trapped on the surface of the fungal cells by an electrostatic interaction between gold ions and negatively charged carboxylate groups, which is facilitated by enzymes that are present in the mycelia’s cell wall. Later, the enzymes in the cell wall reduce the silver ions, causing the development of silver nuclei. These nuclei then increase as more Ag ions are reduced and accumulate on them.

The TEM data demonstrate the presence of some silver nanoparticles both on and inside the cytoplasmic membrane. The findings concluded that the Ag ions that permeate through the cell wall were decreased by enzymes found inside the cytoplasm and on the cytoplasmic membrane. Also possible is the diffusion of some silver nanoparticles over the cell wall and eventual cytoplasmic entrapment ( Mukherjee et al., 2001 ; Hulkoti and Taranath, 2014 ).

It was observed that the culture’s age does not affect the shape of the synthesized gold nanoparticles. However, the number of particles decreased when older cells were used. The different pH levels produce a variety of shapes of gold nanoparticles, indicating that pH plays a vital role in determining the shape. The incubation temperature also played an essential role in the accumulation of the gold nanoparticles. It was observed that the particle growth rate was faster at increased temperature levels ( Mukherjee et al., 2001 ; Ahmad et al., 2003 ). The form of the produced gold nanoparticles was shown to be unaffected by the age of the culture. However, when older cells were utilized, the particle count fell. The fact that gold nanoparticles take on various forms at different pH levels suggests that the pH is crucial in determining the shape. The incubation temperature significantly influenced the accumulation of the gold nanoparticles. It was found that higher temperatures caused the particle development rate to accelerate ( Mukherjee et al., 2001 ; Ahmad et al., 2003 ). Verticillium luteoalbum is reported to synthesize gold nanoparticles of 20–40 nm in size ( Erasmus et al., 2014 ). Aspergillus terreus and Penicillium brevicompactum KCCM 60390 based metal NPs are reported for their antimicrobial ( Li G. et al., 2011 ) and cytotoxic activities ( Mishra et al., 2011 ), respectively.

Biosynthesis of NPs using actinomycetes: Actinomycetes have been categorized as prokaryotes since they share significant traits with fungi. They are sometimes referred to as ray fungi ( Mathew et al., 2010 ). Making NPs from actinomycetes is the same as that of fungi ( Sowani et al., 2016 ). Thermomonospora sp., a new species of extremophilic actinomycete, was discovered to produce extracellular, monodispersed, spherical gold nanoparticles with an average size of 8 nm ( Narayanan and Sakthivel, 2010 ). Metal NPs synthesized by Rhodococcus sp. ( Ahmad et al., 2003 ) and Streptomyces sp. Al-Dhabi-87 ( Al-Dhabi et al., 2018 ) are reported for their antimicrobial activities.

Biosynthesis of NPs using algae: Algae have a high concentration of polymeric molecules, and by reducing them, they may hyper-accumulate heavy metal ions and transform them into malleable forms. Algal extracts typically contain pigments, carbohydrates, proteins, minerals, polyunsaturated fatty acids, and other bioactive compounds like antioxidants that are used as stabilizing/capping and reducing agents ( Khanna et al., 2019 ). NPs also have a faster rate of photosynthesis than their biosynthetic counterparts. Live or dead algae are used as model organisms for the environmentally friendly manufacturing process of bio-nanomaterials, such as metallic NPs ( Hasan, 2015 ). Ag and Au are the most extensively researched noble metals to synthesized NPs by algae either intracellularly or extracellularly ( Dahoumane et al., 2017 ). Chlorella vulgaris ( Luangpipat et al., 2011 ), Chlorella pyrenoidosa ( Eroglu et al., 2013 ), Nanochloropsis oculata ( Xia et al., 2013 ), Scenedesmus sp. IMMTCC-25 ( Jena et al., 2014 ) based metal NPs are reported for their potential catalytic ( Luangpipat et al., 2011 ; Eroglu et al., 2013 ) and, antimicrobial ( Eroglu et al., 2013 ; Jena et al., 2014 ) activities along with their use in Li-Ion batteries ( Xia et al., 2013 ).

Intracellular synthesis of NPs using algae: In order to create intracellular NPs, algal biomass must first be gathered and thoroughly cleaned with distilled water. After that, the biomass (living algae) is treated with metallic solutions like AgNO3. The combination is then incubated at a specified pH and a specific temperature for a predetermined time. Finally, it is centrifuged and sonicated to produce the extracted stable NPs ( Uzair et al., 2020 ).

Extracellular synthesis of NPs using algae: Algal biomass is first collected and cleaned with distilled water before being used to synthesize NPs extracellularly ( Uzair et al., 2020 ). The following three techniques are frequently utilized for the subsequent procedure:

(i) A particular amount of time is spent drying the algal biomass (dead algae), after which the dried powder is treated with distilled water and filtered.

(ii) The algal biomass is sonicated with distilled water to get a cell-free extract.

(iii) The resultant product is filtered after the algal biomass has been rinsed with distilled water and incubated for a few hours (8–16 h).

5.2.6.2. Biological synthesis using plant extracts

The substance or active ingredient of the desired quality extracted from plant tissue by treatment for a particular purpose is a plant extract ( Jadoun et al., 2021 ). Plant extracts are combined with a metal salt solution at room temperature to create nanoparticles. Within minutes, the response is finished. This method has been used to create nanoparticles of silver, gold, and many other metals ( Li X. et al., 2011 ). Nanoparticles are biosynthesized using a variety of plants. It is known that the kind of plant extract, its concentration, the concentration of the metal salt, the pH, temperature, and the length of contact time all have an impact on how quickly nanoparticles are produced as well as their number and other properties ( Mittal and Chisti, 2013 ). A leaf extract from Polyalthia longifolia was used to create silver nanoparticles, the average particle size was around 58 nm ( Kumar and Yadav, 2009 ; Kumar et al., 2016 ).

Acacia auriculiformis ( Saini et al., 2016 ), Anisomeles indica ( Govindarajan et al., 2016 ), Azadirachta indica ( Velusamy et al., 2015 ), Bergenia ciliate ( Phull et al., 2016 ), Clitoria ternatea , Solanum nigrum ( Krithiga et al., 2013 ), Coffea arabica ( Dhand et al., 2016 ), Coleus forskohlii ( Naraginti et al., 2016 ), Curculigo orchioides ( Kayalvizhi et al., 2016 ), Digitaria radicosa ( Kalaiyarasu et al., 2016 ), Dioscorea alata ( Pugazhendhi et al., 2016 ), Diospyros paniculata ( Rao et al., 2016 ), Elephantopus scaber ( Kharat and Mendhulkar, 2016 ), Emblica officinalis ( Ramesh et al., 2015 ), Euphorbia antiquorum L. ( Rajkuberan et al., 2017 ), Ficus benghalensis ( Nayak et al., 2016 ), Lantana camara ( Ajitha et al., 2015 ), Cinnamomum zeylanicum ( Soni and Sonam, 2014 ), and Parkia roxburghii ( Paul et al., 2016 ) are the few examples of plants which are reported for the green synthesis of metal NPs (i.e., AgNPs). These were evaluated for their antifilaria activity ( Saini et al., 2016 ), mosquitocidal activity ( Govindarajan et al., 2016 ), antibacterial activity ( Velusamy et al., 2015 ), catalytic activity ( Edison et al., 2016 ), antioxidant activity ( Phull et al., 2016 ), and Cytotoxicity ( Patil et al., 2017 ).

5.2.6.3. Biological synthesis using biomimetic

“Biomimetic synthesis” typically refers to chemical processes that resemble biological synthesis carried out by living things ( Dahoumane et al., 2017 ). In the biomimetic approach, proteins, enzymes, cells, viruses, pollen, and waste biomass are used to synthesize NPs. Two categories are used to classify biomimetic synthesis:

Functional biomimetic synthesis uses various materials and approaches to emulate particular characteristics of natural materials, structures, and systems ( Zan and Wu, 2016 ).

Process biomimetic synthesis is a technique that aims to create different desirable nanomaterials/structures by imitating the synthesis pathways, processes, or procedures of natural chemicals and materials/structures. For instance, several distinctive nano-superstructures (such as satellite structures, dendrimer-like structures, pyramids, cubes, 2D nanoparticle arrays, 3D AuNP tubes, etc.) have been put together in vitro by simulating the protein manufacturing process ( Zan and Wu, 2016 ).

6. Applications of NPs

6.1. applications of nps in environment industry.

Due to their tiny size and distinctive physical and chemical characteristics, NPs appeal to various environmental applications. The properties of nanoparticals and their advantages are illustrated in Figure 4 . The following are some possible NP uses in the environment.

Properties of nanoparticals and their advantages.

6.1.1. Bioremediation

Nanoparticles (NPs) can remove environmental pollutants, such as heavy metals from water or organic contaminants from soil ( Zhuang and Gentry, 2011 ). For example, silver nanoparticles (AgNPs) effectively degrade certain pollutants, such as organic dyes and compounds found in wastewater. Several nanomaterials have been considered for remediation purposes, such as nanoscale zeolites, metal oxides, and carbon nanotubes and fibers ( Zhuang and Gentry, 2011 ). Nanoscale particles used in remediation can access areas that larger particles cannot. They can be coated to facilitate transport and prevent reaction with surrounding soil matrices before reacting with contaminants. One widely used nanomaterial for remediation is Nanoscale zerovalent iron (nZVI). It has been used at several hazardous waste sites to clean up chlorinated solvents that have contaminated groundwater ( Elliott et al., 2013 ). Removing heavy metals such as mercury, lead, thallium, cadmium, and arsenic from natural water has attracted considerable attention because of their adverse effects on environmental and human health. Superparamagnetic iron oxide NPs are an effective sorbent material for this toxic soft material. So, no measurements of engineered NPs in the environment have been available due to the absence of analytical methods able to quantify the trace concentration of NPs ( Elliott et al., 2013 ).

6.1.2. Sensors in environment

Nanotechnology/NPs are already being used to improve water quality and assist in environmental clean-up activities ( Pradeep, 2009 ). Their potential use as environmental sensors to monitor pollutants is also becoming viable NPs can be used as sensors to detect the presence of certain compounds in the environment, such as heavy metals or pollutants. The nano-sensors small size and wide detection range provide great flexibility in practical applications. It has been reported that nanoscale sensors can be used to detect microbial pathogens and biological compounds, such as toxins, in aqueous environments ( Yadav et al., 2010 ). NPS can be designed to selectively bind to specific types of pollutants, allowing them to be detected at low concentrations. For example, gold nanoparticles (AuNPs) have been used as sensors for the detection of mercury in water ( Theron et al., 2010 ).

6.1.3. Catalysts in environment

Nanoparticles (NPs) are used as catalysts in chemical reactions, such as in the production of biofuels or environmental remediation processes, and to catalyze biomass conversion into fuels, such as ethanol or biodiesel. For example, platinum nanoparticles (PtNPs) have been explored for use in the production of biofuels due to their ability to catalyze the conversion of biomass into fuels ( Lam and Luong, 2014 ). PtNPs also showed promising sensing properties; for example, Using Pt NPs, the Hg ions were quantified in the range of 50–500 nM in MilliQ, tap, and groundwater samples, and the limit of quantifications for Hg ions were 16.9, 26, and 47.3 nM. The biogenic PtNPs-based probe proved to be applicable for detecting and quantifying Hg ions ( Kora and Rastogi, 2018 ).

Overall, NPs have significant potential for use in the environment and are being actively researched for a variety of applications.

6.2. Applications of NPs in medicine industry

Nanoparticles (NPs) have unique physical and chemical properties due to their small size, making them attractive for use in various applications, including the medicine industry. Some potential applications of NPs in medicine include:

6.2.1. Drug delivery

Technological interest has been given to AuNPs due to their unique optical properties, ease of synthesis, and chemical stability. The particles can be used in biomedical applications such as cancer treatment ( Sun et al., 2014 ), biological imaging ( Abdulle and Chow, 2019 ), chemical sensing, and drug delivery. Sun et al. (2014) mentioned in detail about two different methods of controlled release of drugs associated with NPs, which were (1) sustained (i.e., diffusion-controlled and erosion-controlled) and (2) stimuli-responsive (i.e., pH-sensitive, enzyme-sensitive, thermoresponsive, and photosensitive). Figure 5 illustrates that how NPs acts as targeted delivery of medicines to treat cancer cells ( Figure 5A ) and therapeutic gene delivery to synthesis proteins of interests in targeted cells ( Figure 5B ). NPs can deliver drugs to specific body areas, allowing for more targeted and effective treatment ( Siddique and Chow, 2020 ). For example AgNPs have been explored for use in drug delivery due to their stability and ability to accumulate in certain types of cancerous tumors ( Siddique and Chow, 2020 ). ZnONPs have also been explored for drug delivery due to their ability to selectively target cancer cells ( Anjum et al., 2021 ). CuNPs have been shown to have antimicrobial properties and are being explored for drug delivery to treat bacterial infections ( Yuan et al., 2018 ). AuNPs have unique optical, electrical, and catalytic properties and are being explored for drug delivery due to their ability to accumulate in certain cancerous tumors. Silver NPs (AgNPs) have been incorporated into wound dressings, bone cement, and implants ( Schröfel et al., 2014 ).

Application of nanoparticles as; targated drug delivery (A) , and therapeutic protein generation in targated cells (B) .

6.2.2. Diagnostics

Nanoparticles (NPs) can be used as imaging agents to help visualize specific body areas. For example, iron oxide nanoparticles (Fe 3 O 4 NPs) have been used as magnetic resonance imaging (MRI) contrast agents to help visualize tissues and organs ( Nguyen et al., 2013 ). AuNPs have unique optical, electrical, and catalytic properties and are being explored for diagnostics due to their ability to accumulate in certain cancerous tumors ( Siddique and Chow, 2020 ).

6.2.3. Tissue engineering

Nanoparticles (NPs) can help stimulate the growth and repair of tissues and organs. For example, titanium dioxide nanoparticles (TiO2 NPs) have been explored for tissue engineering due to their ability to stimulate the growth of bone cells ( Kim et al., 2014 ).

6.2.4. Antimicrobials

Some NPs, such as silver nanoparticles (AgNPs) and copper nanoparticles (CuNPs), have strong antimicrobial properties and are being explored for use in a variety of medical products, such as wound dressings and medical devices ( Hoseinzadeh et al., 2017 ).

Overall, NPs have significant potential for use in the medical industry and are being actively researched for various applications. However, it is essential to carefully consider the potential risks and benefits of using NPs in medicine and ensure their safe and responsible use.

6.3. Applications of NPs in agriculture industry

There are several ways in which nanoparticles (NPs) have the potential to alter the agricultural sector. NPs may be used in agriculture for a variety of reasons, including:

6.3.1. Pesticides and herbicides

Nanoparticles (NPs) can be used to deliver pesticides and herbicides in a targeted manner, reducing the number of chemicals needed and minimizing the potential for environmental contamination ( Khan et al., 2019 ). AgNPs and CuNPs have antimicrobial properties, making them potentially useful for controlling pests and diseases in crops. They can also be used as delivery systems for active ingredients, allowing for more targeted application and reducing the potential for environmental contamination ( Hoseinzadeh et al., 2017 ; Dangi and Verma, 2021 ).

It is important to note that using metal NPs in pesticides and herbicides is still in the early stages of development. More research is needed to understand their potential impacts on human health and the environment ( Dangi and Verma, 2021 ).

6.3.2. Fertilizers and plant growth

Nano fertilizers offer an opportunity for efficiently improving plant mineral nutrition. Some studies have shown that nanomaterials can be more effective than conventional fertilizers, with a controlled release of nutrients increasing the efficiency of plant uptake and potentially reducing adverse environmental outcomes associated with the loss of nutrients in the broader environment. However, other studies have found that nanomaterial has the same or even less effective effectiveness than conventional fertilizers. NPs used to deliver fertilizers to plants more efficiently, reducing the amount of fertilizer needed, and reducing the risk of nutrient runoff ( Kopittke et al., 2019 ).

Ag ( Jaskulski et al., 2022 ), Zn ( Song and Kim, 2020 ), Cu, Au, Al, and Fe ( Kopittke et al., 2019 ) based NPs have been shown to have fertilizing properties and plant growth-promoting properties, and may help provide essential nutrients to plants and improve plant growth and yield. It is important to note that the use of NPs in fertilizers is still in the early stages of development. More research is needed to understand their potential impacts on human health and the environment.

6.3.3. Food safety

Nanoparticles (NPs) can detect and eliminate pathogens in food products, improving food safety, and reducing the risk of foodborne illness ( Zhuang and Gentry, 2011 ).

6.3.4. Water purification

Nanoparticles (NPs) can purify irrigation water, reducing the risk of crop contamination and improving crop yield ( Zhuang and Gentry, 2011 ). Using NPs in agriculture can improve crop yields, reduce agriculture’s environmental impact, and improve food products’ safety and quality.

6.4. Applications of NPs in food industry

Numerous applications for nanoparticles (NPs) in the food sector are possible, including:

6.4.1. Food processing and food preservation/food packaging

Nanoparticles (NPs) can be used to improve the efficiency and performance of food processing operations, such as grinding, mixing, and drying, e.g., AgNPs have been used as a natural antimicrobial agent in food processing operations, helping to prevent the growth of bacteria and other microorganisms ( Dangi and Verma, 2021 ) and also NPs are used to enhance the performance of materials used in food packaging, making them more resistant to pollutants like moisture and gases.

6.4.2. Food fortification

Nanoparticles (NPs) can deliver essential nutrients to food products, such as vitamins and minerals, more efficiently and effectively. e.g., Fe 2 O 3 , and CuNPs have been used to fortify food products with iron, and Cu is an essential nutrient necessary for the metabolism of iron and other nutrients. Iron is an essential nutrient often lacking in many people’s diets, particularly in developing countries ( Kopittke et al., 2019 ).

6.4.3. Sensors

Nanoparticles (NPs) used to improve the sensitivity and specificity of food sensors, allowing them to detect a broader range of substances or signals ( Yadav et al., 2010 ).

Overall, using NPs in the food industry can improve the performance, safety, and nutritional value of a wide range of food products and processes.

6.5. Applications of NPs in electronics industry and automotive industry

In many aspects, nanoparticles (NPs) can transform the electronics sector. NPs may be used in a variety of electrical applications, such as:

6.5.1. Display technologies/storage devices

Nanoparticles (NPs) can be used to improve the performance of displays ( Park and Choi, 2019 ; Bahadur et al., 2021 ; Triana et al., 2022 ), such as LCD and OLED displays, by enhancing the brightness, color, and contrast of the image, such as silver NPs and gold NPs, have been explored for use in LCD and OLED displays as a means of improving the conductivity of the display ( Gwynne, 2020 ). NPs improve the performance and durability of energy storage devices, such as batteries and supercapacitors, by increasing energy density and charging speed. Zinc oxide nanoparticles (ZnO NPs) have the potential to be used in energy storage devices, such as batteries and supercapacitors, due to their ability to store and release energy ( Singh et al., 2011 ).

6.5.2. Data storage

Nanoparticles (NPs) can improve the capacity and speed of data storage devices, such as hard drives and flash drives. Magnetic NPs, such as iron oxide NPs, have been explored for use in data storage devices, such as hard drives, due to their ability to store, and retrieve data using magnetism. These NPs are often composed of a magnetic metal, such as iron, cobalt, or nickel. They can be magnetized and demagnetized, allowing them to store and retrieve data ( Ahmad et al., 2021 ).

Overall, the use of NPs in electronics has the potential to improve the performance and efficiency of a wide range of electronic devices and systems.

Applications of NPs in chemical industry: The chemical industry might be entirely transformed by nanoparticles (NPs) in various ways. The following are potential uses for NPs in the chemical industry ( Salem and Fouda, 2021 ).

6.5.3. Chemical processing/catalysis

Nanoparticles (NPs) can be used as catalysts in chemical reactions, allowing them to be carried out more efficiently and at lower temperatures. Some examples of metal NPs that have been used as catalysts in the chemical industry include: PtNPs have been used as catalysts in a variety of chemical reactions, including fuel cell reactions ( Bhavani et al., 2021 ), hydrogenation reactions, and oxidation reactions ( Lara and Philippot, 2014 ), PdNPs have been used as catalysts in a variety of chemical reactions, including hydrogenation reactions and cross-coupling reactions ( Pérez-Lorenzo, 2012 ), FeNPs have been used as catalysts in a variety of chemical reactions, including hydrolysis reactions ( Jiang and Xu, 2011 ), and oxygen reduction reactions, NiNPs have been used as catalysts in a variety of chemical reactions, including hydrogenation reactions, and hydrolysis reactions ( Salem and Fouda, 2021 ).

6.5.4. Separation and purification

NPs are used to separate and purify chemicals and other substances, such as gases and liquids, by exploiting their size-based properties ( Hollamby et al., 2010 ). Several types of metal nanoparticles (NPs) have been explored for use in separation and purification processes in the chemical industry, including Fe 2 O 3 NPs have been used to separate and purify gases, liquids, and chemicals. They have also been used to remove contaminants from water ( Pradeep, 2009 ; Siddique and Chow, 2020 ). AgNPs have been used to purify water and remove contaminants ( Pradeep, 2009 ), such as bacteria and viruses. They have also been used to remove heavy metals from water and other substances ( Zhuang and Gentry, 2011 ). AuNPs have been used to purify water and remove contaminants, such as bacteria and viruses ( Siddique and Chow, 2020 ). They have also been used to separate and purify gases and liquids ( Zhuang and Gentry, 2011 ). AlNPs have been used to remove contaminants from water and other substances, such as oils and fuels. They have also been used to purify gases ( Zhuang and Gentry, 2011 ).

6.6. Applications of NPs in defense industry

Nanoparticles (NPs) can be used to improve the efficiency and performance of chemical processing operations, such as refining and synthesizing chemicals ( Schröfel et al., 2014 ). Nanoparticles (NPs) have the potential to be used in the defense industry in several ways, including:

6.6.1. Sensors

Nanoparticles (NPs) can improve the sensitivity and specificity of sensors used in defense systems, such as sensors for detecting chemical, biological, or radiological threats ( Zheng et al., 2010 ).

6.6.2. Protective coatings

Nanoparticles (NPs) can improve the performance and durability of protective coatings applied to defense equipment, such as coatings resistant to chemical or biological agents. For example, metal NPs can improve the mechanical properties and durability of the coating, making it more resistant to wear and corrosion. For example, adding Al or Zn based NPs to a polymer coating can improve its corrosion resistance. In contrast, adding Ni or Cr-based NPs can improve their wear resistance ( Rangel-Olivares et al., 2021 ).

6.6.3. Weapons

Nanoparticles (NPs) are used as weapons against viruses, bacteria, etc, ( Ye et al., 2020 ) and as well as in the development of armor and protective materials. There have been some reports of the potential use of NPs in military and defense applications, such as in the development of armor and protective materials. For example, adding nanoparticles, such as ceramic or metal NPs, to polymers or other materials can improve their mechanical properties and make them more resistant to damage. In addition, there have been reports of the use of NPs in developing sensors and detection systems for defense purposes.

6.6.4. Manufacturing

Nanoparticles (NPs) can improve the performance and durability of materials used in defense equipment, such as armor or structural materials. Metal NPs can be used in materials by adding them as a filler or reinforcement in polymers. For example, the addition of metal NPs such as aluminum (Al), copper (Cu), or nickel (Ni) to polymers can improve the mechanical properties, thermal stability, and electrical conductivity of the resulting composite material ( Khan et al., 2019 ).

Metal NPs can also make functional materials, such as catalysts and sensors. For example, metal NPs, such as gold (Au), and platinum (Pt), can be used as catalysts in various chemical reactions due to their high surface area and ability to adsorb reactants ( Zheng et al., 2010 ).

6.6.5. Energy storage

Nanoparticles (NPs) can improve the performance and efficiency of energy storage systems used in defense systems, such as batteries or fuel cells ( Morsi et al., 2022 ). In batteries, nanoparticles can be used as a cathode material to increase the battery’s energy density, rate capability, and cycling stability. For example, lithium cobalt oxide (LiCoO 2 ) nanoparticles have been used as cathode materials in lithium-ion batteries due to their high capacity and good rate performance. In addition, nanoparticles of transition metal oxides, such as iron oxide (Fe 2 O 3 ), and manganese oxide (MnO 2 ), have been used as cathode materials in rechargeable lithium batteries due to their high capacity and good rate performance. In supercapacitors, nanoparticles can be used as the active material in the electrodes to increase the specific surface area, leading to an increase in the device’s capacitance ( Morsi et al., 2022 ). Using NPs in the defense industry can improve defense systems’ performance, efficiency, and safety.

7. Future perspectives

Metal nanoparticles (NPs) have many potential applications in various fields, including electronics, energy storage, catalysis, and medicine. However, there are also several challenges and potential future directions for developing and using metal NPs.

One major challenge is synthesizing and processing metal NPs with precise size and shape control. Many methods for synthesizing metal NPs involve high temperatures and harsh chemical conditions, which can be challenging to scale up for large-scale production. In addition, the size and shape of metal NPs can significantly impact their properties and potential applications, so it is essential to synthesize NPs with precise size and shape control.

Another challenge is the environmental impact of metal NPs. Some metal NPs, such as silver NPs, can be toxic to aquatic life and may have other environmental impacts. There is a need for more research on the environmental effects of metal NPs and the development of more environmentally friendly (Green) synthesis and processing methods.

In terms of future directions, one promising area is the use of metal NPs for energy storage, conversion, and protection of the environment. For example, metal NPs could be used to improve batteries’ performance or develop more efficient solar cells. In addition, metal NPs could be used in catalysis to improve the efficiency of chemical reactions. There is also ongoing research on metal NPs in medicine, including drug delivery and cancer therapy.

Author contributions

KAA: conceptualization, methodology, validation, formal analysis, investigation, writing – original draft, writing – review and editing, and visualization.

Acknowledgments

The author thanks Prof. Dr. Mona M. Sobhy, Department of Reproductive Diseases, Animal Reproduction Research Institute, ARC, Giza, Egypt, and Dr. Omar Hewedy, University of Guelph, Canada, for the critical reading of the manuscript.

Conflict of interest

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Submission of the Manuscript

Manuscripts has to be submitted via on-line platform j.uctm.edu. Every submitted manuscript obtains automatically a reference number in the on-line system.

Manuscript preparation

The file has to be prepared in a MS word format. All contributions should be typed in a single column, double-spaced, 12-pt font. All pages must be consecutively numbered. Most formatting codes will be removed and replaced on processing the article. Do not embed graphically designed equations or tables, but prepare these using the MS word tools . Use Tab function to start new paragraph.

Essential title page information

Title. It should be concise and informative. Titles are often used in information-retrieval systems. It has to be presented in uppercase. Avoid abbreviations and formulae where possible.

Author names and affiliations. The names of the authors have to be clearly indicated and numbered by superscripted consecutive Arabic numerals when they have different affiliations. The authors’ affiliation addresses (where the actual work was done) including the full postal address of each affiliation, as well as the country name and e-mails of all authors followed by names’ abbreviations in brackets have to be presented below the names. Any change in the authors ' names after proof of the manuscript is not acceptable.

Corresponding author. Clearly indicate by underlying who will handle correspondence at all stages of refereeing and publication, also post-publication.

Present/permanent address. If the author has moved since the work described in the article was done, or was visiting at the time, a “Present address” (or “Permanent address”) may be indicated as a footnote to that author’s name. The address at which the author actually did the work must be retained as the main, affiliation address. Superscript Arabic numerals are used for such footnotes.

ARTICLE STRUCTURE

Please do not number any sections of the manuscript. Subsections have to be presented in bold, normal letters starting with a capital one without numbering.

A concise and factual abstract is required. The ab stract should state briefly the purpose of the research, the principal results and major conclusions. The abstract will be presented separately from the article on the web site of the journal, so it must be able to stand

alone. For this reason, using of References should be avoided, but if essential, then cite the author(s) and year(s). Also, nonstandard or uncommon abbreviations should be avoided. No more than eight keywords have to be presented during submission process.

INTRODUCTION

State the objectives of the work and provide an adequate background. Avoid a detailed literature survey or a summary of the results.

EXPERIMENTAL

Provide sufficient details to allow the work to be reproduced. Methods already published should be indicated by a reference and briefly described.

RESULTS AND DISCUSSION

Results and the discussion provided should be clear and concise.

CONCLUSIONS

The main conclusions of the study have to be presented in a short Conclusions section marked with points.

Acknowledgements

Acknowledgements have to be presented in a separate section at the end of the article before the references.

References should be cited in the text by an Arabic numeral in square brackets, listed numerically and typed double-spaced on a separate sheet at the end of the paper. They should be arranged in the order in which they appear in the text. Journal titles should be abbreviated according to the latest Chemical Abstracts Service Source Index. Only articles that have been published should be included in the references. Avoid citing articles in press if possible. Unpublished results should be cited as such in the text. References in non-English language should be translated in English. The original language must be shown in brackets at the end of citation. In the reference list, the styling, punctuation and capitalization should be as follows:

For journals:

T. Komatsu, T. Honma, K. Shinozaki, Design of crystal orientation and morphology by laser patterning in glasses, J. Chem. Technol. Metall., 50, 4, 2015, 367-374.

A. Krueger, Carbon Materials and Nanotechnology, Weinheim, WILEY-VCH Verlag GmbH & Co. KGaA, 2010.

For edited books:

F.W. Cooke, J.E. Lemons, B.D. Ratner, in: B.D. Ratner, A.S. Hoffman, F.J. Lemons (Eds.), Biomaterials

Science, Academic Press, San Diego, 1996, p. 11.

For conference proceedings, symposia, etc.:

1. E. Motta, D. Rajpathak, Z. Zdrahal, R. Roy, The Epistemology of Scheduling Problems, F.V. Harmelen (ed.), Proceedings of the 15 th European Conference on Artificial Intelligence, Lyon, France, 2002, 215-219.

2. S. Savov, Research and optimization of cone inertial crusher technological parameters, ISBN 978-619-160-906-2, Avangard Prima Ltd, 2017, Sofia, (in Bulgarian).

Citing of the papers published in Journal of Chemical Technology and Metallurgy should be done using the abbreviation of the title as follows:

J. Chem. Technol. Metall.

Formulae should be typewritten (Equation Editor) with ample space around them. The meanings of all symbols have to be given immediately after the equation in which they are first used. Equations should be sequentially numbered (on the full right side of the paper, in the same line and in parentheses). Subscripts and superscripts should be clearly indicated. Use an interval around mathematical signs both in the text and in the formulae.

Units should be given in SI system. They should be in the form, e.g. g cm -1 rather than g/cm. An interval must be left between the number and the units, including %.

Figures should be numbered consecutively with Arabic numerals. All figures have to be also submitted on separate files. They should also accompany the manuscript. Photographs, charts and diagrams must all to be referred as “Fig. 1.”. They should be numbered consecutively in the order to which they are referred. The figures should not include text. They have to be presented in TIFF or JPG with resolution higher than 300 dpi. Authors must take into account that Journal of Chemical Technology and Metallurgy has a printed version and all figures have to be prepared readable in the gray scale. All illustrations should be clearly marked with the figure number. Figure captions should be typed double-spaced on a separate sheet at the end of the manuscript.

Tables should be numbered consecutively with Arabic numerals in the order of appearance in the text. Each table should be given on separate sheet with a short descriptive title directly above it, with essential footnotes below, if necessary, in 8 pt font. When preparing tables use all grids for each row and column.

Academia.edu no longer supports Internet Explorer.

To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to  upgrade your browser .

Enter the email address you signed up with and we'll email you a reset link.

• We're Hiring!
• Help Center

Chemical Technology

Related Papers

Nicolas K. Scholtes

Macromolecular Bioscience

Hans Mooibroek

International Journal of Engineering …

Usman Hamza

roopkishor rajak

Minister Obonukut

Shahwaize Saleem

introduction

Carbon Capture and Storage (CCS) technology has begun to transform into the boom of CO2 utilization technology, which is of great significance to China considering its coal-based primary energy mix. CO2 utilization technology can be divided into three categories, i.e., CO2 geological utilization (CGU), CO2 chemical utilization, and CO2 biological utilization. In this paper, first, the development status of the different utilization technologies in China is introduced, and then, the situation, distribution, and water characteristics of China’s Coal Chemical Industry (CCI, i.e., an industry to convert coal to synthetic fuel and/or chemical products) are analyzed in detail. Subsequently, utilization technologies suitable for China’s CCI are proposed combining water consumption of CCS technology. The results of this research led to the following conclusions: (1) CO2 utilization technology is undoubtedly the best choice for the CCI; (2)CGUtechnologies are viewed as the best choices for the coal chemical industry, with supplementary, small-scale chemical utilization of three wastes, i.e., waste gas, wastewater, and industrial residue; (3) The CO2-Enhanced Oil Recovery (EOR), CO2-Enhanced Uranium Leaching (EUL), CO2-Enhanced Coal Bed Methane recovery (ECBM), and CO2-Enhanced (Saline) Water Recovery (EWR) technologies show great promise, and CCI preferentially uses the option with low water consumption, such as CO2-EWR. However, as the carbon market matures, CO2-EOR will become the first priority.

Abdullah Aitani

Chemical Engineering Research & Design

charlene cheng

A debate has begun on the potential for renewable raw materials (RRM) to substitute fossil hydrocarbons in synthetic products. A related debate has arisen in the liquid fuels sector with contested proposals for the expansion of biofuels production. A transition to integrated biorefineries as analogues of oil refineries has been advocated, to enable RRM to compete with petroleum and minimise environmental impacts. Transitions between technological systems involve evolutionary processes, in which change emerges from reinforcing feedbacks between different levels of the socio-technical system. The past both shapes the current system and influences and constrains future options and pathways. Thus, over the past half century oil refiners and the associated petrochemical industry have achieved a high level of integration that challenges the competitive development of RRM, for which the full range of necessary technologies and product families are not well established and the commercial and technical risks are high. This paper explores a case study of the transition from coal-based to petrochemical feedstocks in the UK (1921–1967), applying a system dynamics approach to extract and elucidate the key interrelationships between technologies, policy and society. The findings and insights are then used to inform a discussion of scenarios for future biorefinery technologies, with a focus on bio-based chemicals.

Ternenge Joseph Chior , Hezekiah Ogo Agogo

Nigeria recently endorsed the World Bank's zero routine flaring by 2030 initiative and raised her own goal to 2020. As a step towards achieving the 2020 flare out goal, the Ministry of Petroleum Resources has established a national gas flare commercialization framework. Under this framework, licenses would be issued to third parties who would become off-takers of the gas. While this framework presents opportunity for investment, most of the oil fields where the gas is being flared may be far from existing pipelines and process infrastructures. Additionally, flare gas is often associated with volume, composition and pressure fluctuations, which make technology selection for its utilization more challenging. This paper reviewed some technologies for flare gas recovery and utilization, and identified promising technologies with capabilities of handling flare gas volume below 1 MMscfd. Mini gas-to-liquid (mini-GTL) technologies for producing diesel, methanol and anhydrous ammonia developed by Greyrock, GasTechno and Proton Ventures, respectively, were selected. The technical viability and economic benefits of these technologies were evaluated based on feed gas rate of 500 Mscfd. While all the technologies are technically viable, the gross profit margin of the GasTechno's miniGTL technology with methanol as the GTL product was found to be more attractive.

RELATED PAPERS

Timothy LIPMAN

Industrial & Engineering Chemistry Research

K. Al-qahtani

•   We're Hiring!
•   Help Center
• Find new research papers in:
• Health Sciences
• Earth Sciences
• Cognitive Science
• Mathematics
• Computer Science
• Academia ©2024

• Chemical Engineering
• Chemical Technology - I (Web) 
• Co-ordinated by : IIT Roorkee
• Available from : 2013-11-12
• Chemical Process Industries
• Raw Material for Organic Chemical Industries
• Basic Principles of Unit Processes & Unit Operations in Organic Chemical Industries
• Coal as Chemical Feed Stock
• Coal carbonization and Coke Oven Plant
• Gasification of Coal, Petrocoke and Biomass
• Introduction to Pulp and Paper Industry, Raw Material for Paper Industry and Technological Development
• Pulping and Bleaching
• Recovery of Chemicals from Kraft and Agrobased Mills
• Stock Preparation and Paper Making
• Introduction to Soap and Detergent, Soap Making and Recovery of Glycerine
• Synthetic Detergent and Linear Alkyl Benzene
• Introduction to Sugar , Fermentation Industry and Manufacture of Alcohol
• Ethanol as Chemical Feedstock
• Introduction : Status of Petroleum Refinery, Crude Oil and Natural Gas Origin, Occurrence, Exploration, Drilling and Processing, Fuel Norms
• Evaluation of Crude Oil, Petroleum Products and Petrochemicals
• Crude Oil Distillation
• Thermal Cracking, Visbreaking and Delayed Coking
• Catalytic Cracking, Fluid Catalytic Cracking and Hydro Cracking
• Catalytic Reforming
• Alkylation, Isomerisation and Polymerisation
• Desulphurisation Processes and Recovery of Sulphur
• Profile of Petrochemical Industry and its Structure
• Naphtha and Gas Cracking for Production of Olefins
• Recovery of Chemicals from FCC and Steam Cracker
• Synthesis Gas and its Derivatives: Hydrogen, CO, Methanol, Formaldehyde, Metanol to Olefin Technology
• Ethylene and Derivatives: Ethylene Oxide, Ethylene Glycol, Ethylene Dichloride and Vinyl Chloride, Acetaldehyde
• Propylene, Propylene Oxide and Isopropanol, Acrylonitrile
• Aromatic (BTX) Production
• Aromatics Product Profile, Ethyl benzene &Styrene, Cumene and Phenol, Bisphenol, Aniline
• Introduction to Polymer, Elastomer and Synthetic Fibre, Classification Polymerisation Reactions and Polymer
• Polymer: Polyolefins: Polyethylene, Poly Propylene and Polystyrene
• Polyvinyl chloride, Polycarbonate, Thermoset Resin:Phenol Formaldehyde, Urea Formaldehyde and Melamine Formaldehyde
• Elastomers: Natural and Synthetic Rubber , Styrene Butadiene Rubber(SBR), Poly Butadiene, Nitrile Rubber
• Cylohexane, Caprolactam, Nylon 6 Adipic Acid and Hexametrhylenediamine, Nylon66
• DMT and Terephthalic Acid, Polyester, PET Resin, PBT Resin
• Acrylonitrile, Acrylic Fibre, Modified Acrylic Fibre, Polyurethane
• Cellulosic Fibre(Viscose Rayon and Acetate Rayon, Cuprammoium rayon)
• Agrochemical Market
• Dyes and Intermediate
• Web Content

MIT Technology Review

• Newsletters

Google DeepMind’s new AlphaFold can model a much larger slice of biological life

AlphaFold 3 can predict how DNA, RNA, and other molecules interact, further cementing its leading role in drug discovery and research. Who will benefit?

• James O'Donnell archive page

Google DeepMind has released an improved version of its biology prediction tool, AlphaFold, that can predict the structures not only of proteins but of nearly all the elements of biological life.

It’s a development that could help accelerate drug discovery and other scientific research. The tool is currently being used to experiment with identifying everything from resilient crops to new vaccines. 

While the previous model, released in 2020, amazed the research community with its ability to predict proteins structures, researchers have been clamoring for the tool to handle more than just proteins. 

Now, DeepMind says, AlphaFold 3 can predict the structures of DNA, RNA, and molecules like ligands, which are essential to drug discovery. DeepMind says the tool provides a more nuanced and dynamic portrait of molecule interactions than anything previously available. 

“Biology is a dynamic system,” DeepMind CEO Demis Hassabis told reporters on a call. “Properties of biology emerge through the interactions between different molecules in the cell, and you can think about AlphaFold 3 as our first big sort of step toward [modeling] that.”

AlphaFold 2 helped us better map the human heart , model antimicrobial resistance , and identify the eggs of extinct birds , but we don’t yet know what advances AlphaFold 3 will bring. 

Mohammed AlQuraishi, an assistant professor of systems biology at Columbia University who is unaffiliated with DeepMind, thinks the new version of the model will be even better for drug discovery. “The AlphaFold 2 system only knew about amino acids, so it was of very limited utility for biopharma,” he says. “But now, the system can in principle predict where a drug binds a protein.”

Isomorphic Labs, a drug discovery spinoff of DeepMind, is already using the model for exactly that purpose, collaborating with pharmaceutical companies to try to develop new treatments for diseases, according to DeepMind. 

AlQuraishi says the release marks a big leap forward. But there are caveats.

“It makes the system much more general, and in particular for drug discovery purposes (in early-stage research), it’s far more useful now than AlphaFold 2,” he says. But as with most models, the impact of AlphaFold will depend on how accurate its predictions are. For some uses, AlphaFold 3 has double the success rate of similar leading models like RoseTTAFold. But for others, like protein-RNA interactions, AlQuraishi says it’s still very inaccurate. 

DeepMind says that depending on the interaction being modeled, accuracy can range from 40% to over 80%, and the model will let researchers know how confident it is in its prediction. With less accurate predictions, researchers have to use AlphaFold merely as a starting point before pursuing other methods. Regardless of these ranges in accuracy, if researchers are trying to take the first steps toward answering a question like which enzymes have the potential to break down the plastic in water bottles, it’s vastly more efficient to use a tool like AlphaFold than experimental techniques such as x-ray crystallography. 

A revamped model  

AlphaFold 3’s larger library of molecules and higher level of complexity required improvements to the underlying model architecture. So DeepMind turned to diffusion techniques, which AI researchers have been steadily improving in recent years and now power image and video generators like OpenAI’s DALL-E 2 and Sora. It works by training a model to start with a noisy image and then reduce that noise bit by bit until an accurate prediction emerges. That method allows AlphaFold 3 to handle a much larger set of inputs.

That marked “a big evolution from the previous model,” says John Jumper, director at Google DeepMind. “It really simplified the whole process of getting all these different atoms to work together.”

It also presented new risks. As the AlphaFold 3 paper details, the use of diffusion techniques made it possible for the model to hallucinate, or generate structures that look plausible but in reality could not exist. Researchers reduced that risk by adding more training data to the areas most prone to hallucination, though that doesn’t eliminate the problem completely. 

Restricted access

Part of AlphaFold 3’s impact will depend on how DeepMind divvies up access to the model. For AlphaFold 2, the company released the open-source code , allowing researchers to look under the hood to gain a better understanding of how it worked. It was also available for all purposes, including commercial use by drugmakers. For AlphaFold 3, Hassabis said, there are no current plans to release the full code. The company is instead releasing a public interface for the model called the AlphaFold Server , which imposes limitations on which molecules can be experimented with and can only be used for noncommercial purposes. DeepMind says the interface will lower the technical barrier and broaden the use of the tool to biologists who are less knowledgeable about this technology.

Artificial intelligence

Sam altman says helpful agents are poised to become ai’s killer function.

Open AI’s CEO says we won’t need new hardware or lots more training data to get there.

What’s next for generative video

OpenAI's Sora has raised the bar for AI moviemaking. Here are four things to bear in mind as we wrap our heads around what's coming.

• Will Douglas Heaven archive page

Is robotics about to have its own ChatGPT moment?

Researchers are using generative AI and other techniques to teach robots new skills—including tasks they could perform in homes.

• Melissa Heikkilä archive page

An AI startup made a hyperrealistic deepfake of me that’s so good it’s scary

Synthesia's new technology is impressive but raises big questions about a world where we increasingly can’t tell what’s real.

Stay connected

Get the latest updates from mit technology review.

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at [email protected] with a list of newsletters you’d like to receive.

University of Oxford to lead new Sustainable Chemicals and Materials Manufacturing Research Hub

The University of Oxford is leading a major UK government investment in research to improve the sustainability of chemical and polymer production. The Sustainable Chemicals and Materials Manufacturing Hub (SCHEMA) will bring together researchers from across the UK working with a large consortium of commercial, technology translation and civic partners. The Hub has been funded by £11 million from the UKRI Engineering and Physical Sciences Research Council (EPSRC) and leverages a further £22 million in funding from its partners.

Supply chain partnerships are at the heart of SCHEMA. Our success will also rely on strong advocacy and engagement. Our prior success working with major national and international bodies will be used to support joined-up policy, legislative, and economic environments for the technologies developed in SCHEMA. Professor Charlotte Williams , Department of Chemistry, University of Oxford.

SCHEMA is one of five new manufacturing research hubs announced today by UKRI EPSRC which aim to address a wide range of challenges in commercialising early-stage research within different manufacturing sectors.

Science Minister, Andrew Griffith said: ' Manufacturing accounts for almost a tenth of the UK’s economic output, but for the sector to keep growing and sustaining jobs nationwide, it has to tackle challenges ranging from reducing emissions, to cutting production costs.  These new hubs will support UK researchers with the cutting-edge facilities they need, to help our manufacturers seize the benefits of technologies such as robotics and AI. Harnessing these innovations will cement the UK's position as a global leader in sustainable manufacturing.'

The SCHEMA Hub will be led by Professor Charlotte Williams OBE FRS from the University of Oxford’s Department of Chemistry, and will involve academics from Chemistry, Engineering, Materials Science, Computation, Environmental Economics, and Law at the Universities of Oxford, Bath, Liverpool, Cardiff, York and Cambridge.

Professor Williams said: ‘It is imperative that the chemical industry reaches net zero emissions and sustainability as so many essential downstream industries depend upon it. Our Hub will be well placed to tackle this difficult challenge by bringing together a very wide range of academic expertise with companies from across the supply chain.’

The research focusses on transforming the way chemicals and polymers are designed, made, and recycled. This includes supporting the transition away from the use of virgin petrochemicals and redesigning processes and materials to increase recycling rates. A key focus will be to design processes that can produce chemicals and polymers from renewable raw materials such as biomass, carbon dioxide, and even industrial wastes, and integrating renewable energy into the process engineering. This will build upon the University Oxford’s research on transforming carbon dioxide and biomass wastes into plastics, elastics, adhesives, and coatings .

Within SCHEMA, researchers will work with a range of partners including businesses, catapults , professional societies, and international academic partners to tackle the shared materials design and sustainability challenges of important end-use sectors. These partnerships will enable sustainable chemicals and polymers to be designed for immediate use within key sectors including electronics, transportation, energy generation and storage, construction, and fast-moving consumer goods.

At launch, the team are supported by 25 companies from across the supply chain, representing polymer and material end-users.

The Hub seeks to ensure that the UK remains at the forefront of major international efforts to transition to sustainable chemical manufacturing. The research program will train a new generation of postdoctoral and early career researchers to take on leadership roles in UK sustainable chemical manufacturing.

Professor Charlotte Deane , EPSRC Executive Chair, and a Professor in Oxford University’s Department of Statistics, said: ‘Given the scale and importance of the UK’s manufacturing sector we must ensure that it is able to benefit fully from advances made across the research and innovation ecosystem. With their focus on innovation and sustainability the advances made by the hubs will benefit specific sectors, the wider manufacturing sector and economy, as well the environment.’

Finding new ways to sustainably make things is a challenge of our age. It is quite right that University plays its part. The SCHEMA Hub is a collaborative venture engaging academia, industry, and policymakers. The hub will rethink and reformulate chemical production, making it not just environmentally friendly, but an engine of innovation and progress for generations to come. Professor Jim Naismith, Head of Mathematical, Physical and Life Sciences Division at the University of Oxford

Chemical manufacturing is crucial to the UK’s economy. It is the UK’s second largest manufacturing industry, directly employing over 140,000 people and delivering turnover exceeding £75 bn/yr . However, there is an urgent need for this industry to tackle the environmental impact from both manufacturing and its products. Greenhouse gas emissions from the global sector are significant, with it currently accounting for approximately 5–6% of emissions , which is 2–3 times larger than the global airline industry . Coupled to this are the challenges of raw material being sourced from fossil fuel extraction and refining, pollution in water and soil, and globally low rates of polymer recycling.

The academics working in SCHEMA have strong track records in commercial partnership and entrepreneurship. For example, Hub EDI champion Professor Kylie Vincent is a founder of HydRegen , which applies innovative chemo-enzymatic processes to make chemicals. The Hub is strongly integrated with high-tech and growth SMEs as well as multinationals. It builds upon the successful partnerships established in the Oxford and Bath-led Innovation Centre for Applied Sustainable Technologies.

For further information about the EPSRC SCHEMA Hub please contact Professor Charlotte Williams and Dr Greg Sulley .

DISCOVER MORE

• Support Oxford's research
• Partner with Oxford on research
• Study at Oxford
• Research jobs at Oxford

You can view all news or browse by category

• You are here:
• American Chemical Society
• Discover Chemistry

‘Forever chemicals’ found to rain down on all five Great Lakes

FOR IMMEDIATE RELEASE

“The Ins and Outs of Per- and Polyfluoroalkyl Substances in the Great Lakes: The Role of Atmospheric Deposition” Environmental Science & Technology

Perfluoroalkyl and polyfluoroalkyl substances, also known as PFAS or “forever chemicals,” have become persistent pollutants in the air, water and soil. Because they are so stable, they can be transported throughout the water cycle, making their way into drinking water sources and precipitation. According to findings published in ACS’ Environmental Science & Technology , precipitation introduces similar amounts of PFAS into each of the Great Lakes; however, the lakes eliminate the chemicals at different rates.

Consuming PFAS has been linked to negative health outcomes. And in April 2024, the U.S. Environmental Protection Agency (EPA) designated two forever chemicals — PFOS and PFOA — as hazardous substances, placing limits on their concentrations in drinking water. The Great Lakes are a major freshwater source for both the U.S. and Canada, and the EPA reports that the surrounding basin area is home to roughly 10% and 30% of each country’s population, respectively. Previous studies demonstrated that these lakes contain PFAS. But Marta Venier at Indiana University and colleagues from the U.S. and Canada wanted to understand where the compounds come from and where they go.

Between 2021 and 2022, 207 precipitation samples and 60 air samples were taken from five sites surrounding the Great Lakes in the U.S.: Chicago; Cleveland; Sturgeon Point, N.Y.; Eagle Harbor, Mich.; and Sleeping Bear Dunes, Mich. During the same period, 87 different water samples were collected from the five Great Lakes. The team analyzed all the samples for 41 types of PFAS and found:

• ·In precipitation samples, PFAS concentrations largely remained the same across sites, suggesting that the compounds are present at similar levels regardless of population density.
• In air samples, Cleveland had the highest median concentration of PFAS and Sleeping Bear Dunes the lowest, suggesting a strong connection between population density and airborne PFAS.
• In the lake water samples, the highest concentration of PFAS were in Lake Ontario, followed by Lake Michigan, Lake Erie, Lake Huron and Lake Superior.
• ·The concentration of PFOS and PFOA in lake water decreased compared to data from previous studies as far back as 2005, but the concentration of a replacement PFAS known as PFBA remained high, suggesting that further regulation efforts may be needed.

The team calculated that airborne deposition from precipitation is primarily how PFAS get into the lakes, while they’re removed by sedimentation, attaching to particles as they settle to the lakebed or flowing out through connecting channels. Overall, their calculations showed that the northernmost lakes (Superior, Michigan and Huron) are generally accumulating PFAS. Further south, Lake Ontario is generally eliminating the compounds and levels in Lake Erie remain at a steady state. The researchers say that this work could help inform future actions and policies aimed at mitigating PFAS’ presence in the Great Lakes. 

The authors acknowledge funding from the Great Lakes Restoration Initiative from the U.S. Environmental Protection Agency’s Great Lakes National Program Office.

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News . ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.

To automatically receive press releases from the American Chemical Society, contact newsroom@acs.org .

Note: ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies.

Media Contact

ACS Newsroom newsroom@acs.org

Related Content

More From This Series

Accept & Close The ACS takes your privacy seriously as it relates to cookies. We use cookies to remember users, better understand ways to serve them, improve our value proposition, and optimize their experience. Learn more about managing your cookies at Cookies Policy .

1155 Sixteenth Street, NW, Washington, DC 20036, USA |  service@acs.org  | 1-800-333-9511 (US and Canada) | 614-447-3776 (outside North America)

• Terms of Use
• Accessibility

Copyright © 2024 American Chemical Society