twelve principles for environmentally conscious chemistry
1. Prevent waste Design chemical syntheses to prevent waste, leaving no waste to treat or clean up.
2. Design safer chemicals & products Design chemical products to be fully effective, yet have little or no toxicity.
3. Design less hazardous chemical syntheses Design syntheses to use and generate substances with little or no toxicity to humans and the environment.
4. Use renewable feedstocks Use raw materials and feedstocks that are renewable rather than depleting. Renewable feedstocks are often made from agricultural products or are the wastes of other processes; depleting feedstocks are made from fossil fuels (petroleum, natural gas, or coal) or are mined.
5. Use catalysts, not stoichiometric reagents Minimize waste by using catalytic reactions. Catalysts are used in small amounts and can carry out a single reaction many times. They are preferable to stoichiometric reagents, which are used in excess and work only once.
6. Avoid chemical derivatives Avoid using blocking or protecting groups or any temporary modifications if possible. Derivatives use additional reagents and generate waste.
7. Maximize atom economy Design syntheses so that the final product contains the maximum proportion of the starting materials. There should be few, if any, wasted atoms.
8. Use safer solvents & reaction conditions Avoid using solvents, separation agents, or other auxiliary chemicals. If these chemicals are necessary, use innocuous chemicals.
9. Increase energy efficiency Run chemical reactions at ambient temperature and pressure whenever possible.
10. Design chemicals & products to degrade after use Design chemical products to break down to innocuous substances after use so that they do not accumulate in the environment.
11. Analyse in real time to prevent pollution Include in-process real time monitoring and control during syntheses to minimize or eliminate the formation of by-products.
12. Minimize the potential for accidents Design chemicals and their forms (solid, liquid or gas) to minimize the potential for chemical accidents including explosions, fires and releases to the environment.
*Paul Anastas and John Warner, 1998. Green Chemistry: Theory and Practice, Oxford University Press: New York