绿色化学（slideworld） green chemistry.ppt

GreenChemistry,GREENCHEMISTRY,DEFINITIONGreenChemistryistheutilisationofasetofprinciplesthatreducesoreliminatestheuseorgenerationofhazardoussubstancesinthedesign,manufactureandapplicationofchemicalproducts.GREENCHEMISTRYISABOUTWasteMinimisationatSourceUseofCatalystsinplaceofReagentsUsingNon-ToxicReagentsUseofRenewableResourcesImprovedAtomEfficiencyUseofSolventFreeorRecyclableEnvironmentallyBenignSolventsystems,GreenChemistryIsAbout.,Cost,Waste,Materials,Hazard,Risk,Energy,Reducing,Chemistryisundeniablyaveryprominentpartofourdailylives.Chemicaldevelopmentsalsobringnewenvironmentalproblemsandharmfulunexpectedsideeffects,whichresultintheneedforgreenerchemicalproducts.AfamousexampleisthepesticideDDT.,WhydoweneedGreenChemistry?,GreenchemistrylooksatpollutionpreventiononthemolecularscaleandisanextremelyimportantareaofChemistryduetotheimportanceofChemistryinourworldtodayandtheimplicationsitcanshowonourenvironment.TheGreenChemistryprogramsupportstheinventionofmoreenvironmentallyfriendlychemicalprocesseswhichreduceoreveneliminatethegenerationofhazardoussubstances.ThisprogramworksverycloselywiththetwelveprinciplesofGreenChemistry.,The12PrinciplesofGreenChemistry(1-6),7UseofRenewableFeedstocksArawmaterialorfeedstockshouldberenewableratherthandepletingwhenevertechnicallyandeconomicallypracticable.8ReduceDerivativesUnnecessaryderivatization(useofblockinggroups,protection/de-protection,andtemporarymodificationofphysical/chemicalprocesses)shouldbeminimisedoravoidedifpossible,becausesuchstepsrequireadditionalreagentsandcangeneratewaste.9CatalysisCatalyticreagents(asselectiveaspossible)aresuperiortostoichiometricreagents.10DesignforDegradationChemicalproductsshouldbedesignedsothatattheendoftheirfunctiontheybreakdownintoinnocuousdegradationproductsanddonotpersistintheenvironment.11Real-timeAnalysisforPollutionPreventionAnalyticalmethodologiesneedtobefurtherdevelopedtoallowforreal-time,in-processmonitoringandcontrolpriortotheformationofhazardoussubstances.12InherentlySaferChemistryforAccidentPreventionSubstancesandtheformofasubstanceusedinachemicalprocessshouldbechosentominimisethepotentialforchemicalaccidents,includingreleases,explosions,andfires.,The12PrinciplesofGreenChemistry(7-12),“Itisbettertopreventwastethantotreatorcleanupwasteafteritisformed”,ChemicalProcess,“Theuseofauxiliarysubstances(e.g.solvents,separationagents,etc.)shouldbemadeunnecessarywhereverpossible,andinnocuouswhenused”,“Energyrequirementsshouldberecognizedfortheirenvironmentalimpactsandshouldbeminimized.Syntheticmethodsshouldbeconductedatambientpressureandtemperature”,HeatingCoolingStirringDistillationCompressionPumpingSeparation,EnergyRequirement(electricity),Burnfossilfuel,CO2toatmosphere,GLOBALWARMING,“Arawmaterialoffeedstockshouldberenewableratherthandepletingwherevertechnicallyandeconomicallypractical”,Non-renewable,Renewable,ResourceDepletion,Renewableresourcescanbemadeincreasinglyviabletechnologicallyandeconomicallythroughgreenchemistry.,Biomass,Nanoscience,Solar,Carbondioxide,Wasteutilization,Polylacticacid(PLA)forplasticsproduction,Polyhydroxyalkanoates(PHAs),EnergyGlobalChangeResourceDepletionFoodSupplyToxicsintheEnvironment,ThemajorusesofGREENCHEMISTRY,Energy,Thevastmajorityoftheenergygeneratedintheworldtodayisfromnon-renewablesourcesthatdamagetheenvironment.CarbondioxideDepletionofOzonelayerEffectsofmining,drilling,etcToxics,Energy,GreenChemistrywillbeessentialindevelopingthealternativesforenergygeneration(photovoltaics,hydrogen,fuelcells,biobasedfuels,etc.)aswellascontinuethepathtowardenergyefficiencywithcatalysisandproductdesignattheforefront.,GlobalChange,Concernsforclimatechange,oceanictemperature,stratosphericchemistryandglobaldistillationcanbeaddressedthroughthedevelopmentandimplementationofgreenchemistrytechnologies.,ResourceDepletion,Duetotheoverutilizationofnon-renewableresources,naturalresourcesarebeingdepletedatanunsustainablerate.Fossilfuelsareacentralissue.,ResourceDepletion,Renewableresourcescanbemadeincreasinglyviabletechnologicallyandeconomicallythroughgreenchemistry.BiomassNanoscience&technologySolarCarbondioxideChitinWasteutilization,FoodSupply,Whilecurrentfoodlevelsaresufficient,distributionisinadequateAgriculturalmethodsareunsustainableFuturefoodproductionintensityisneeded.Greenchemistrycanaddressmanyfoodsupplyissues,FoodSupply,Greenchemistryisdeveloping:Pesticideswhichonlyaffecttargetorganismsanddegradetoinnocuousby-products.Fertilizersandfertilizeradjuvantsthataredesignedtominimizeusagewhilemaximizingeffectiveness.Methodsofusingagriculturalwastesforbeneficialandprofitableuses.,ToxicsintheEnvironment,Substancesthataretoxictohumans,thebiosphereandallthatsustainsit,arecurrentlystillbeingreleasedatacostoflife,healthandsustainability.Oneofgreenchemistrysgreateststrengthsistheabilitytodesignforreducedhazard.,IncreasingGreenness,Prevention&Reduction,Recycling&Reuse,Treatment,Disposal,PollutionPreventionHierarchy,Conclusion,Green