Green chemistry? What a weird name?

GREEN chemistry does not refer to the colour of the reactants used in a special branch of chemistry, rather it refers to how chemistry can help the environment.

Green chemistry can be defined as the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances.

This term was coined in 1991 by Dr. Paul Anatas, and is also referred to as sustainable chemistry. This article introduces the concept of green chemistry.

To fully understand green chemistry, you have to understand its 12 principles. The first principle is that synthetic chemicals are designed so that their use generates few toxins or none at all.

Another principle is to prevent waste, so by using these synthetic chemicals in place of the harmful ones, no waste is produced so there is no waste to be treated or cleaned up.

One product of chemical reactions is derivatives, this means that extra reagents are used which results in the production of waste. In this principle, the production of waste is also minimised through the use of catalysts. With catalysts, a small amount is needed not only to carry out the reaction once but multiple times. This is the opposite of what are known as stoichiometric reagents where large amounts of the chemical is needed to produce a single reaction.

This leads to the next principle which is to design chemicals and products that are safer to use in terms of their effect on the environment. Some chemical reactions only occur when there is an increase in temperature. This temperature increase is possible with more energy, usually from electricity supplied through the burning of fossil fuels. However, through green chemistry, the reactions that occur between the synthesised chemicals can run at room temperature and pressure so that no extra energy is required.

Some reactions also involve the use of solvents and chemicals to separate compounds, in addition to other chemicals. The use of these chemicals are unavoidable for some reactions to take place, but through green chemistry one can use safer versions of these chemicals to do the same job.

One principle of green chemistry is to use renewable starting materials or feedstocks.

Often these feedstocks are fossil fuels, whereas renewable sources include agricultural products or the waste generated from other processes. Another principle of green chemistry is to design chemicals that degrade after they are used, a sort of self-destruct mechanism if you will. The objective in this case is that they will not accumulate in the environment after they are used.

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Green chemistry? What a weird name?