Green chemistry
- Also known as
- sustainable chemistry, 12 principles of green chemistry
Green chemistry is the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances. It is commonly framed by the Twelve Principles of Green Chemistry set out by Paul Anastas and John Warner in 1998.
What is green chemistry?
Green chemistry aims to prevent pollution at its source, by designing chemicals and the processes that make them so that hazards are reduced from the start, rather than managing waste and exposure afterward. The U.S. Environmental Protection Agency and the American Chemical Society’s Green Chemistry Institute both promote it, and it is widely used as a framework for evaluating new products.
The twelve principles
Anastas and Warner’s principles, in brief:
- Prevent waste rather than treat it.
- Maximize atom economy, so more of the raw materials end up in the product.
- Use and generate less hazardous substances in syntheses.
- Design safer chemicals that do their job with less toxicity.
- Use safer solvents and auxiliaries, or avoid them.
- Design for energy efficiency, ideally at ambient temperature and pressure.
- Use renewable feedstocks where practical.
- Reduce unnecessary chemical steps.
- Prefer catalytic reactions.
- Design products to break down after use; see biodegradability.
- Monitor processes in real time to prevent pollution.
- Choose inherently safer chemistry to minimize accidents.
Green chemistry in practice
In formulated products, green chemistry shows up as ingredients with lower toxicity and better biodegradability, reduced volatile organic compounds, renewable feedstocks, and manufacturing that uses less energy and hazardous material. Biomanufacturing, which uses living systems at moderate temperatures with renewable feedstocks, is often discussed in this context.
Frequently asked questions
The terms overlap and are often used interchangeably. Sustainable chemistry is sometimes used more broadly to include economic and social dimensions.
Not automatically. Renewable feedstocks are one principle of green chemistry, but a bio-based product can still be hazardous or made by a wasteful process.
Sources
- Green Chemistry: Theory and Practice, P. T. Anastas and J. C. Warner, Oxford University Press, 1998
- Basics of green chemistry, U.S. Environmental Protection Agency
- 12 Principles of Green Chemistry, American Chemical Society Green Chemistry Institute