欢迎来到天天文库
浏览记录
ID:27688929
大小:1.47 MB
页数:156页
时间:2018-12-03
《碳纤维材料的性能与应》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、SomeresearchDiscoveryresearchaimedatidentifyinga100%-selectiveactivesiteisongoingbothinindustryandinacademia.Anexample:acatalystthatdecreasesby-productpollutantCCl4selectivityduringthemanufactureofphosgenehasbeenrecentlydiscovered.Theconventionalcoconutcarbon-basedcatalystp
2、roducedabout500ppmofCCl4intheexhaust,whichhadtobereducedtobelow100ppmtomeetthetighterregulations.ThenewcatalysthasreducedCCl4levelstobelow50ppmandproducesmorephosgeneComputationalchemistryisbeingincreasinglyusedtoprobetheactivesite.Thereisaneedfortoolsthatrepresentandtrackm
3、olecularspeciesincomplexfeeds.Thisisespeciallytrueinpetroleumrefining.Molecularmodelingisbeingusedtoestimatetransportcoefficientsinzeolites(Theodorouetal.,1996).Thereisacontinuingneedtoextendtheworktomorecomplexfeedandcatalystsystems.Processtechnologyfortheon-sitemanufactur
4、eandimmediateuseofhazardouschemicalseliminatestheneedtotransport,storeandhandlehazardouschemicals.Analternateapproachtoon-sitegenerationistodeveloptechnologythatrendersmaterialsnon-hazardouspriortoshipping.Anexample:usedinthedeliveryofHCNtominesitesforgoldextraction,istored
5、ucetheriskofexposurebyconvertingHCNtosolidNaCNpriortoshipment.Thereisanactiveinterestinfindingnewusesforby-productsorconvertingby-productstousefulproducts.Volatileorganiccompound(VOC)controlThetwoprimaryoptionsfordestroyingVOCsarebythermalorcatalyticoxidation.Thermaloxidize
6、rs(combustiondevices):achievehighdestructionefficiencyifproperlyoperatedatthe3Ts:temperature,turbulence,andresidencetime.Catalyticoxidizersmaybebeadbedsormonoliths.Theactivecatalyticingredients(usuallynoblemetals)aretypicallysupportedonahighsurfaceareaalumina(Spivey,1987).C
7、atalyticsystemscantypicallyoperateatamuchlowerexcessoxygenconcentrationthanthermaloxidizers.Nitrogenoxides(NOx)controlNitrogenoxidesareprimarilyformedbytheoxidationoffuel-boundnitrogenandbyreactionofair-derivednitrogenwithoxygenathightemperature.reducinghightemperaturehotsp
8、ots,increasingturbulence,andincreasingtheresidencetime.Anotherapproachisthedevelop
此文档下载收益归作者所有