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Green Chemistry
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Green Chemistry Without chemical products our standard of living would drop significantly. Can society have the advantages of chemical products without the potential harm to the environment and human health? The answer is yes. Green chemistry is the name given to the effort to change or reinvent these processes in order to ensure a safer, cleaner environment in the 21st century. Green chemistry aims to eliminate pollution by preventing it from happening in the first place and by using resources for chemical products that are renewable.
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Green Chemistry The other key component of green chemistry is to close the cycle in chemical production so that there is little to no waste product. In designing a reaction according to green chemistry principles, chemists pay close attention to whatever is known about the possible hazards a chemical presents to health or the environment before using that chemical in a reaction or creating it as a product. In other words, they treat the hazard posed by a substance as a property that must be considered along with other chemical and physical properties and select substances that minimize harm.
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What is Green Chemistry
Green chemistry, also called sustainable chemistry, is a philosophy of chemical research and engineering that encourages the design of products and processes that minimize the use and generation of hazardous substances. Becoming “greener” involves changing manufacturing process so that it is less harmful to the environment.
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GREEN CHEMISTRY IS ABOUT
Waste Minimization at Source Use of Catalysts Using Non-Toxic Reagents Use of Renewable Resources Improved Atom Efficiency Use of Solvent Free or Recyclable Environmentally Solvent systems
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The 12 Principles of Green Chemistry
Prevention It’s better to prevent waste than to treat or clean up waste afterwards. Atom Economy Design synthetic methods to maximize the incorporation of all materials used in the process into the final product. Less Hazardous Chemical Syntheses Design synthetic methods to use and generate substances that minimize toxicity to human health and the environment. Designing Safer Chemicals Design chemical products to affect their desired function while minimizing their toxicity. Safer Solvent Minimize the use of substances wherever possible make them innocuous when used. Design for Energy Efficiency Minimize the energy requirements of chemical processes and conduct synthetic methods at ambient temperature and pressure if possible.
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The 12 Principles of Green Chemistry
Use of Renewable Feedstocks Use renewable raw material or feedstock rather whenever practicable. Reduce Derivatives Minimize or avoid unnecessary derivatization if possible, which requires additional reagents and generate waste. Catalysis Catalytic indicators are superior to other indicators. Design for Degradation Design chemical products so they break down into innocuous products that do not persist in the environment. Real-time Analysis for Pollution Prevention Develop analytical methodologies needed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances. Inherently Safer Chemistry for Accident Prevention Choose substances and the form of a substance used in a chemical process to minimize the potential for chemical accidents, including releases, explosions, and fires.
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Funny way to show the Principles of Green Chemistry
ATrTV-4
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Green Chemistry Is About...
Waste Materials Hazard Risk Energy Environmental Impact Cost Re Reducing
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Waste and The Chemical Industry
Where does the waste come from? • Areas traditionally thought of as being dirty (oil refining & bulk chemical production) are relatively clean - they need to be since margins per Kg are low. • Newer industries with higher profit margins and employing more complex chemistry produce much more waste relatively. Industry Segment Tonnage Ratio Kg Byproduct/kg Products Oil Refining < 0.1 Bulk Chemicals 1-5 Fine chemicals 5-50 Pharmaceuticals
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Pollution prevention Hierarchy
Prevention & Reduction Recycling & Reuse Increasing Greenness Treatment Disposal
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http://www.youtube.com/watch?v=4PYx s8KBBHQ
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