- Also called:
- sustainable chemistry
- Key People:
- Yves Chauvin
- Richard R. Schrock
- Robert H. Grubbs
- Related Topics:
- chemistry
- environmentalism
green chemistry
-
What is green chemistry?
Green chemistry is an approach to chemical research and industrial processes that aims to reduce or eliminate pollution by improving how chemicals are designed, manufactured, and used. Also called sustainable chemistry, green chemistry focuses on designing chemical products and processes that are safer for humans and the environment, minimize waste, and are energy efficient.
The 12 principles of green chemistry provide a framework for chemists to use when designing or selecting chemical products or processes:
1. Prevent waste
2. Maximize atom economy
3. Synthesize less-hazardous chemical by-products
4. Design safer, less-toxic chemical products
5. Use safer solvents and auxiliaries
6. Design energy-efficient chemical-manufacturing processes
7. Use renewable feedstocks
8. Reduce or avoid the production of derivatives
9. Use catalysts
10. Design chemicals that degrade into harmless products after use
11. Analyze chemical products in real time to prevent the formation of hazardous substances
12. Use safer forms of substances to prevent accidents4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
Why is green chemistry important for the environment?
Green chemistry is important because it aims to prevent or reduce pollution through the improved design, manufacture, and use of chemicals. It focuses on reducing the production of hazardous substances, rather than managing them after they're created. The field promotes waste prevention, maximizes production efficiency, uses safer solvents, and designs energy-efficient processes. By using renewable feedstocks and catalysts, green chemistry minimizes by-products and promotes the creation of chemicals that break down into harmless substances. Ultimately, it seeks to create chemical products and processes that are safer for both humans and the environment.
2 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How does green chemistry differ from traditional chemistry?
Green chemistry seeks to minimize pollution by improving the design, manufacture, and use of chemicals. Unlike traditional chemistry, which often focuses on managing hazardous substances after they are produced, green chemistry aims to prevent or reduce the production of these substances in the first place.
The principles of green chemistry include preventing waste, maximizing atom economy, using safer solvents, designing energy-efficient processes, and using renewable feedstocks. By emphasizing the reduction or elimination of hazardous substances, green chemistry strives to create chemical processes and products that are safer for both humans and the environment.
5 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
What are some common principles of green chemistry?
Green chemistry focuses on designing chemical products and processes that are safer for the environment and humans by minimizing waste and maximizing energy efficiency.
Key principles include:
* Waste prevention Preventing waste is preferable to treating or cleaning up waste after it has been created.
* Atom economy Atom economy maximizes the efficiency of production so that fewer by-products are made during the manufacture of the final product. It considers all reactants and products to provide a reliable indicator of whether the reaction produces undesirable by-products or pollutants.
* Less hazardous chemical syntheses Synthesizing less-hazardous chemical by-products and designing safer, less-toxic chemical products.
* Catalysis Using catalysts can reduce material requirements for chemical reactions. Catalysts increase the rate of a reaction without being consumed.
* Safer solvents and auxiliaries Using safer solvents and auxiliaries in chemical processes.4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
Can you give examples of green chemistry in everyday life?
Green chemistry seeks to design chemical products and processes that minimize or eliminate hazardous substances. It emphasizes waste prevention, energy efficiency, and the use of renewable resources.
Everyday examples of green chemistry:
* Bioplastics Bioplastics are plastics made from renewable resources. Some are biodegradable, reducing pollution and reliance on petroleum.
* Degradable Plastics Plastic rings for canned drinks that degrade when exposed to sunlight, reducing litter.
* Greener solvents Safer solvents are used in dyeing textiles, which reduces pollution.
* Alternative dying mediums Using solvents other than water to dye textiles reduces water pollution and energy consumption.5 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How can green chemistry help solve global problems like pollution?
Green chemistry is an approach that aims to prevent pollution by improving how chemicals are designed, manufactured, and used. It focuses on designing chemical products and processes that are safer for humans and the environment, minimize waste, and are energy efficient.
The field provides a specific research agenda through its 12 principles, which include preventing waste, maximizing production efficiency, synthesizing less-hazardous chemicals, using safer solvents, promoting energy-efficient manufacturing, and designing chemicals that degrade into harmless products. By following these principles, green chemistry reduces the production of pollutants, addresses health hazards, ecological risks, and resource efficiency across a product's lifecycle.
2 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
green chemistry, an approach to chemistry that endeavours to prevent or reduce pollution. This discipline also strives to improve the yield efficiency of chemical products by modifying how chemicals are designed, manufactured, and used.
Green chemistry dates from 1991, when the U.S. Environmental Protection Agency (EPA) launched the Alternative Synthetic Pathways for Pollution Prevention research program under the auspices of the Pollution Prevention Act of 1990. This program marked a radical departure from previous EPA initiatives in emphasizing the reduction or elimination of the production of hazardous substances, as opposed to managing these chemicals after they were manufactured and released into the environment. This research program later expanded to include the development of greener solvents and safer chemicals. The name green chemistry was officially adopted in 1996.
The goal of the Pollution Prevention Act of 1990 was not simply to regulate the quantity and type of emissions but to place limits on the industry in order to reduce the amount of pollution it generated. American chemist Paul Anastas, one of the principal founders of green chemistry, claimed that by improving how chemicals are synthesized, it might be possible to prevent the production of pollutants.
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Green chemistry’s 12 principles
To help define a more specific research agenda, the 12 principles of green chemistry were formulated by Anastas and American chemist John Warner in 1998:
- Prevent waste wherever possible.
- Promote “atom economy” (that is, maximize the efficiency of production so that fewer by-products are made during the manufacture of the final product).
- Synthesize less-hazardous chemical by-products.
- Design safer, less-toxic chemical products.
- Use safer solvents and auxiliaries in chemical processes.
- Design energy-efficient chemical-manufacturing processes.
- Use renewable feedstocks.
- Reduce or avoid the production of derivatives.
- Use catalysts (most of which require fewer materials to carry out a chemical reaction).
- Design chemicals that break down into harmless products after they are used.
- Promote the development of real-time analysis of chemical products before hazardous substances can form.
- Promote inherently safer chemistry (such as the use of safer forms of various substances) to prevent accidents from occurring.
Atom economy
Of these principles, “atom economy,” originally suggested by American chemist Barry Trost in 1973, became a central concept among green chemistry researchers. Atom economy was designed to overcome the limitations of the traditional concept of “yield,” the amount of final products, which was used for calculating the efficiency of chemical reactions. To calculate the yield, chemists traditionally considered only the amount of the main chemical product they intended to produce (“target molecules”) and not by-products, which might include environmentally hazardous materials. In contrast, atom economy takes into account all reactants and products and hence provides a more-reliable indicator of whether the reaction produces undesirable by-products—that is, pollutants. Green chemistry has since demonstrated that high-efficiency atom economy is indeed achievable through such processes as hydrogenation, metathesis, and cycloaddition.