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Green chemistry involves applying clean technologies to reduce or eliminate the use and generation of hazardous substances in designing and making chemical products.

The 12 principles of green chemistry

Green chemistry involves 12 principles that have been widely adopted:

1. prevention - aim to prevent waste rather than to treat it or clean up after it
2. atom economy - incorporate all materials into the final product without unwanted side products
3. less hazardous chemical synthesis - where possible, substances should be used and generated that possess little or no toxicity to human health and the environment
4. design safer chemicals - chemical products should be designed to do the job while minimising toxicity
5. safer solvents and auxiliaries - avoid the use of auxiliary substances (solvents, separation agents, etc) wherever possible and ensure they are harmless when they must be used
6. design for energy efficiency - minimise the energy requirements of chemical processes
7. use renewable feedstocks - use renewable raw materials whenever technically and economically possible
8. reduce derivatives - minimise or avoid unnecessary use of derivatives (blocking groups, protection/de-protection, etc) as they generate waste
9. catalysis - catalytic reagents, which can carry out a single reaction many times, are superior to stoichiometric reagents which only work once
10. design for degradation - chemical products should be designed to degrade innocuously at the end of their function
11. real-time analysis for pollution prevention - analytical methodologies are needed for real-time, in-process monitoring and control prior to the formulation of hazardous substances
12. inherently safer chemistry for accident prevention - substances and the form of a substance used in a chemical process should be chosen to minimise the potential for chemical accidents