资源描述：
《液液萃取§11.4萃取设备.ppt》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、1.Inliquid-liquidextraction,asingasabsorptionanddistillation,twophasesmustbebroughtintogoodcontacttopermittransferofmaterialandthenseparated.2.Inabsorptionandindistillation,themixingandseparationareeasyandrapid.Inextraction,however,thetwophaseshavecomparabledensities,sothattheenergyavailablefor
2、mixingandseparation-ifgravityflowisused–issmall,muchsmallerthanwhenphaseisaliquidandtheotherisagas.§11.4ExtractionEquipment（P748）gasabsorption3.Thetwophasesareoftenhardtomixandhardertoseparate.Theviscositiesofbothphasesalsoarerelativelyhigh,andlinearvelocitiesthroughmostextractionequipmentarelo
3、w.4.Insometypesofextractors,therefore,energyformixingandseparationissuppliedmechanically.§11-4ExtractionEquipment机械能，这是吸收和蒸馏所不需要的。5.Extractionequipmentmaybeoperatedbatchwiseorcontinuously.Aquantityoffeedliquidmaybemixedwithaquantityofsolventinanagitatedvessel,afterwhichthelayersaresettledandsep
4、arated.§11-4ExtractionEquipment稀醋酸溶剂萃取相无水醋酸分层废水萃余相萃取塔恒沸精馏塔回收塔萃取及恒沸精馏提浓醋酸的原则流程6.Theextractisthelayerofsolventplusextractedsolute,andtheraffinateisthelayerfromwhichsolutehasbeenremoved.7.Theextractmaybelighterorheavierthantheraffinate,andsotheextractmaybeshowncomingfromthetopoftheequipmentinsomec
5、aseandfromthebottominothers.Theoperationmay,ofcourse,berepeatedifmorethanonecontactisrequired;butwhenthequantitiesinvolvedarelargeandseveralcontactsareneeded,continuousflowbecomeseconomical.§11-4ExtractionEquipment8.Mostextractionequipmentiscontinuouswitheithersuccessivestagecontacts（级式接触）ordif
6、ferentialcontacts（微分接触）.9.Representativetypes（具有代表性的设备）aremixer-settlers（混合静置器）,verticaltowersofvariouskindsthatoperatebygravityflow,agitatedtowerextractors,andcentrifugalextractors.§11-4ExtractionEquipment10.Thecharacteristicsofvarioustypesofextractionequipmentarelistedintable23.2.Liquid-Liqui
7、dextractioncanalsobecarriedoutusingporousmembranesasdescribedinchapter26.Thismethodhaspromisefordifficultseparation.§11-4ExtractionEquipment双溶剂萃取苛性苏打～纯碱医药和有机药品扰动塔挡板塔孔板塔
