SUGGESTIONS OFFERED BY GREEN CHEMISTRY :• It is better to prevent waste than to treat it• Reduce over consumption of energy• Reduce waste• Avoid exploitation of resources* Reduce the use of auxiliary substances• Energy required must be recognized for their impact and reduced• A raw material of feed stock should be renewable rather than depleting where ever technically possible.
AIMS OF GREEN CHEMISTRY:• PREVENTION AND REDUCTION OF WASTES• Treatment of wastes• Disposal of wastes• Recycle and reuse of wastes.
SOLAR ENERGY:• SOLAR COOKERS AND SOLAR WATER HEATERS HELPS IN THE REDUCTION OF USAGE OF FOSSIL FUELS LIKE• LIQUIFIED PETROLEUM GAS• KEROSINE• COAL, etc…
BIOMASS ENERGY• Cow-dung , various plant materials like the residue after harvesting the crops, vegetable waste and sewage are decomposed in the absence of oxygen to give biogas. It leaves no residues like ash in woods and produces no smoke as in charcoal, coal burning.
BIOMASS ENERGY:• The large-scale utilization of bio waste and sewage material provides a safe and efficient method of waste-disposal besides supplying energy and manure.
BENEFITS OF BIOMASS• Renewable Feedstock• Contributes no net CO2 to the atmosphere• Conserves fossil fuel leading to a securedomestic supply• Platform for making an array of chemicalproducts from what is otherwise considered waste.
ECO FRIENDLY PLASTICS:• Eco friendly plastics are also known as poly lactic acid plastics.• They are manufactured from corn.• Corn—starch—unrefined dextrose— fermentation—lactic acid—monomer— lactide –polymer—PLA –polymer modification –fiber, film bottle, thermo forming.
RECENT TRENDS IN GREEN CHEMISTRY:• PET recycled from 2 litre soda bottles are used in new fleece.• Eliminated chlorine bleach in fabrics• No azo dyes, reduced formaldehyde• Glucose is used as an alternative for benzene in synthesis of Adepic acid.• Corn based poly lacticacid plastics ae used to make carpets.• Diphenyl carbonate is used as an alternative for phosgene.
POLICIES OF GREEN CHEMISTRY *Prevent waste rather than treating it *Use renewable sources of energy • Choose substances so as to minimize the potential for chemical accidents, including releases, explosions, and fires.• Auxiliary substances (solvents, etc.) should be made unnecessary wherever possible and innocuous when used.
DESIGNING GREEN PRODUCTS:• Chemical products should be designed to• Use renewable resources– preserve efficacy of function while reducing toxicity, and break down into innocuous degradation products at the end of their function so that they do not persist in the environment.
BETTERMENT OF ENVIRONMENT• Eliminate nearly 100% of emissions in polymer manufacturing and processing• 30-40% reduction in wastes• Reduce 50% usage of plastics• Replace all solvents and acid based catalysis that have adverse effects with solids ,or greener alternatives.
TWELVE PRINCIPLES OF GREEN CHEMISTRY• Prevention of waste; *Atom economy;* Less hazardous chemical synthesis;• Designing safer chemicals;• Safer solvents and auxiliaries;• Energy efficient;• Renewable feed stocks;
• Reduce derivatives;• Catalysis;• Design for degradation;• Real time analysis for pollution prevention;• Safety.
DDT: *The use of DDT has increased enormously due to its effectiveness against mosquitoes and lice. *DDT is one of the effective insecticide . *It is cheap and less toxic to animals. *But later it was more toxic to fishes. *The chemical stability of DDT and its fat solubilitycompounded the problem. *It takes about 8 years to metabolize half of theamount it assimilates.
• THUS GREEN CHEMISTRY HAPPENS TO BE THE REMEDY FOR VARIOUS ENVIRONMENTAL PROBLEMS LIKE SOIL POLLUTION, FOOD CHAIN MAINTENANCE, WATER AND AIR POLLUTION.• LET’S ASPIRE , ASCEND AND ACHIEVE THE GOALS OF GREEN CHEMISTRY!!!!