Twelve principles of green chemistry
Ans... Here are twelve principles of green chemistry as formulated by P. T anstas and J. C warner,in green chemistry.
1...Prevention:-----
It is better to prevent wast than to treat or Clean up wast aftar it has been created.
2...Atom economy:----
Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product
3...Less hazardous chemical synthesis:---
Wherever practical synthetic methods should be designed to use and generate substances that possess little or no toxicity to people or environment
4...Designing safer chemicals :---
Chemical products should be designed to effect their desired function while minimizing their toxicity
5...safer solvent and auxiliaries:---
The use of auxiliary substances (eg. Solvent or separation agents) should be made unnecessary whenever possible and innocuous when used.
6...Design for energy efficiency:---
Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized.If possible, synthetic method should be conducted at ambient temperature and pressure.
7...Use of Renewable feedstocks:---
A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.
8...Reduce Derivatives:---
Unnecessary derivatization (use of blocking groups, protection / de-protection and temporary modification of physical /chemical processes) should be minimized or avoided possible, because such steps require additional reagents and can generate wast.
9...Catalysis:---
Catalysis reagents (as selective as possible) are superior to stoichiometric reagents.
10...Design for Degradation :---
Chemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment.
11...Real time Analysis for pollution prevention:---
Analytical methodologies need to be further developed to allow for real time in process monitoring and control, prior to the formation of hazardous substances
12...Inherently safer chemistry for safer prevention:--
Substances and the form of the substance used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions and fires
The principles of green chemistry and some examples of there applications to basic and applied research are illustrated bellow:---
prevention of waste:----
it is better to prevent wast then to treat or clean up wast after it is formed . the ability of chemists to redesign chemical transformation to minimize the generation of hazardous wast is an important first step in pollution presentation
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