Green Chemistry is a field of chemistry and chemical engineering that stresses majorly upon the design of products and processes which reduces the utilization and evolution of hazardous substances. It is different from environmental chemistry in a way that it focuses on the effects of polluting chemicals on nature while green chemistry focuses on technological approaches to prevent pollution and decreasing consumption of non-renewable resources.
During 1998, Paul Anastas (Green Chemistry Program at US EPA) and John C. Warner (Polaroid Corporation) published a set of 12 principles to suggest various ways to reduce the environmental and health impacts of chemicals on nature, and also suggest research priorities for the development of green chemistry technologies. The principles include the following concepts:
Principles of green chemistry
Green solvents: These are the solvents consumed in large amounts in various chemical syntheses, cleaning and degreasing. These are different from traditional solvents that are usually toxic or chlorinated. Green solvents are derived from renewable resources that can biodegrade to harmless, naturally occurring product.
Synthetic techniques: Innovative synthetic techniques can provide improved environmental performance, thereby enabling better consistency to the green chemistry principles. In 2005, the Nobel Prize for Chemistry was given for the development of the metathesis method in organic synthesis. Three key developments in green chemistry were identified in the area of organic synthesis:
Carbon dioxide used as blowing agent: In 1996, the Greener Reaction Conditions Award was won by Dow Chemical for their cent percent carbon dioxide blowing agent for polystyrene foam production. They discovered that supercritical carbon dioxide works as good as a blowing agent, without indulging any hazardous substances, permitting the polystyrene to get easily recycled. The carbon dioxide involved in this process is reused from other industries in order to reduce the net carbon production from the process to zero.
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