Green Chemistry

concepts A principled stance Green chemistry A new approach is needed to remould Martyn Poliakoff and Paul Anastas attitudes constructively, and to attract young n Chinese, chemistry is the ‘mixing sci- people to the field of chemistry. Step forward Already, young people are beginning ence’, whereas in Dutch, it’s the ‘separation ‘green chemistry’, which aims to create to perceive chemistry as a key to Iart’. But whatever their nationality, acade- products that are as harmless as possible and mic chemists often do not know in detail how therefore require less regulation. The concept saving our environment rather than a the chemicals they use are made, or how their is enshrined in a set of 12 principles, ranging tool for its destruction. chemistry affects the biosphere. They view from minimizing waste to avoiding accidents. industrial chemistry as meat-eaters view the Individually, these principles are not new; slaughterhouse — the gory details are glossed what is potentially revolutionary is grouping is ‘soft’ science. Although understandable in over and the fate of the waste is ignored. On them together so that chemists can focus on historical contexts, neither view is correct. the other hand, much of the general public using classical chemistry to design products Green chemistry is a new partnership, bring- recoils at the mere mention of ‘chemicals’, yet with less environmental impact. For example, ing together the efforts of industrial and acad- we are all clothed, fed, washed and transport- non-toxic carbon dioxide is now used to make emic research and building rapidly on the past ed by the products of the chemical and phar- lighter, stronger building materials and successes of both. New solvents, feedstocks, maceutical industries. While we benefit from to replace chlorinated organic solvents catalysts and processes, producing everything increased quality and length of life thanks to in chemical reactions and dry-cleaning. from new, biologically derived, renewable chemicals, the industry that makes them is Integrating energy, waste and toxicity issues plastics to lead-free automotive paint, are frequently accused of degrading the Earth. when thinking about new processes and being developed throughout the world. Society relies on chemicals. Like a good reactions has proved to be very effective. Many challenges remain. How can chem- cook, the industrial chemist recycles waste. Although some industrial processes are ical production shift from unsustainable Yet many types of waste are dangerous, leaving efficient, others are extremely wasteful, petroleum feedstocks to renewable biomass? no option but costly disposal. With the global requiring costly handling and disposal of Can some of the vast quantities of carbon population rising and standards of living chemicals. The more stages a chemical process dioxide vented into the atmosphere be increasing, current methods of chemical pro- involves, the more potential it has for creating converted into useful chemicals? Can the duction are unsustainable. As production waste. So green chemistry inspires a kind of environmental impact of agrochemicals be rises to meet demand, waste levels will soar chemical ‘golf match’, in which fewer steps reduced while increasing food production? and landfill sites will be exhausted. Manufac- represent a better environmental ‘score’ — Green chemistry will attract the new genera- turers will be increasingly restricted by envir- and the best result is, of course, a hole in one. tion of chemists needed to solve these prob- onmental legislation; enforcement agencies For example, a new process for producing the lems. Already, young people are beginning to will become increasingly overloaded; and anti-inflammatory drug ibuprofen halves the see chemistry as a key to saving our environ-

BRIAN V. CASE, UNIV. NOTTINGHAM CASE, UNIV. BRIAN V. costs of waste treatment will stifle innovation. number of steps, makes them all catalytic and ment rather than a tool for its destruction. more than doubles the atom efficiency of the Will green chemistry take over all of process. Green chemistry not only leads to chemistry? Far from it — the revolution of cleaner and more efficient processes, but can one generation becomes the orthodoxy of increase profitability by eliminating many of the next. The 12 principles are so obvious the traditional costs of treatment, disposal, that chemists of the future will wonder why liability and regulatory compliance. it took so long to integrate them into the Green chemistry involves more than just mainstream. After all, why make chemicals tidying up existing processes — if it were that wastefully and expensively, when they can be simple, process economics would already be produced cheaply and cleanly? I driving manufacturers in that direction. Martyn Poliakoff is a research professor and Paul Rather, it identifies a need to design new, safer Anastas is a special professor at the School of molecules. Often, the toxicity and the useful- Chemistry, University of Nottingham, ness of a compound arise from different parts University Park, Nottingham NG7 2RD, UK. of the molecule; for example, a couple of strategically placed methyl groups added to a FURTHER READING dye molecule makes it much less toxic but Anastas, P. & Warner, J. Green Chemistry: Theory and leaves its dyeing properties intact. Similar Practice (Oxford Univ. Press, London, 1998). minor structural modifications can increase Anastas, P. & Lankey, R. Chem. Britain 37, 26–29 (2001). the biodegradability of molecules and reduce Hamley, P. A. & Poliakoff, M. Chem. Engineer 72, their environmental impact. Linking struc- 24–27 (2001). ture and toxicity gives synthetic chemists a Ritter, S. K. Chem. Eng. News 79, 24–37 (2001). new perspective, allowing them to design new pesticides that are toxic only to target WEBLINKS organisms, with a fraction of the usual dose, Green chemistry network: and which do not persist in the environment. ± http://www.rsc.org/networks/gcn Green chemistry has captured the imagi- What is green chemistry?: nation of many chemists. But some industrial ± http://www.epa.gov/opptintr/greenchemistry/ chemists believe that their very successful whatis.htm Green future: the world needs cleaner chemistry. efforts at cleaning up have been overlooked, Green chemistry at Nottingham: and some academics fear that green chemistry ± http://www.nottingham.ac.uk/greenchemistry