Qhov Tseem Ceeb Qhov txawv - Azeotropic vs Extractive Distillation
Qhov sib txawv tseem ceeb ntawm azeotropic thiab extractive distillation yog tias nyob rau hauv azeotropic distillation, tsim ntawm azeotrope yog yuav tsum tau cais cov Cheebtsam ntawm ib tug sib tov whereas, nyob rau hauv extractive distillation, tsis muaj azeotrope tsim tshwm sim.
Distillation yog txheej txheem ntawm purifying ib cov kua los ntawm ib tug txheej txheem ntawm cua sov thiab txias. Hauv azeotropic distillation, ib qho azeotrope yog tsim ua ntej kev sib cais ntawm cov khoom sib xyaw. Ib qho azeotrope yog qhov sib xyaw ntawm cov khoom uas muaj qhov kub tsis tu ncua. Nyob rau hauv cov txheej txheem extractive distillation, tsis tas yuav tsim ib qho azeotrope. Nyob rau hauv txoj kev ntawd, ib feem thib peb ntxiv rau binary sib tov. Qhov thib peb tivthaiv no tuaj yeem cuam tshuam qhov kev hloov pauv ntawm cov khoom uas twb muaj lawm.
Azeotropic Distillation yog dab tsi?
Azeotropic distillation yog cov txheej txheem sib cais siv los cais cov khoom sib xyaw los ntawm kev tsim cov azeotrope. Azeotropes yog cov khoom sib xyaw ua ke nrog qhov kub tsis tu ncua. Hom kev sib xyaw no tsis tuaj yeem sib cais rau hauv cov khoom siv los ntawm kev distillation yooj yim vim tias tag nrho cov khoom muaj qhov kub ib yam. Thaum cov azeotropic sib tov yog boiled, qhov feem ntawm cov khoom nyob rau hauv cov kua thiab nws vapor theem yog sib npaug.
Nyob rau hauv azeotropic distillation txoj kev, ib tug tshiab tivthaiv (lub npe hu ua tus entrainer) yog ntxiv rau cov azeotropic sib tov nyob rau hauv thiaj li yuav tsim ib tug tshiab azeotrope uas boils ntawm ib tug qis kub tshaj lub azeotrope uas twb muaj lawm. Tom qab ntawd lub kaw lus muaj ob theem ua kua immiscible nrog cov ntsiab lus kub sib txawv (heterogeneous).
Daim duab 01: Lub Txheej Txheem Sib cais Ethanol (E) los ntawm dej (W) siv Benzene (B)
Piv txwv li, cia peb xav txog kev sib xyaw ntawm ethanol thiab dej. Nws yog lub npe hu ua binary azeotrope vim tias muaj ob lub miscible Cheebtsam hauv qhov sib tov. Yog hais tias benzene ntxiv raws li tus entrainer rau qhov sib tov, nws tuaj yeem cuam tshuam qhov volatility ntawm lwm cov khoom hauv qhov sib tov. Qhov sib tov tam sim no hu ua tertiary azeotrope vim muaj peb yam hauv cov sib tov. Thaum qhov sib tov no yog distilled, nws yog hu ua azeotropic distillation.
Dab tsi yog Extractive Distillation?
Extractive distillation yog cov txheej txheem sib cais uas suav nrog qhov sib ntxiv ntawm qhov thib peb rau kev sib xyaw binary kom tso cai rau kev sib cais ntawm ob lub ntsiab lus. Txawm li cas los xij, qhov thib peb tivthaiv tsis vaporize thaum lub sijhawm distillation; qhov thib peb tivthaiv yuav tsum tsis tshua muaj volatile. Los yog lwm yam, nws yuav tsum muaj qhov kub siab dua.
Yog tias qhov sib xyaw binary muaj ob qhov sib xyaw nrog cov ntsiab lus kub zoo sib xws, ces cov khoom no tsis tuaj yeem sib cais los ntawm kev distillation yooj yim. Qhov no tshwm sim vim hais tias ob qho tib si yuav vaporized ntawm ze li ntawm qhov kub zoo sib xws (kev daws teeb meem tsis zoo).
Daim duab 02: Ib qho Kev Qhia Txog Kev Siv Distillation ntawm A thiab B sib tov siv E Solvent
Thaum lub sijhawm cov txheej txheem rho tawm distillation, ib qho azeotrope tsis tsim. Cov txheej txheem cuam tshuam nrog cov kuab tshuaj uas tsis tshua muaj volatility raws li qhov hnyav ntawm cov khoom sib xyaw. Nws yog lub npe hu ua cov kuab tshuaj sib cais. Thaum lub sij hawm distillation, cov khoom uas muaj siab tshaj volatility yuav vaporized yooj yim raws li cov khoom sab saum toj. Cov seem yog cov kuab tshuaj thiab lwm yam khoom (hauv binary sib tov). Txij li thaum cov kuab tshuaj tsis tsim ib qho azeotrope nrog cov khoom thib ob, nws kuj tuaj yeem sib cais tau yooj yim nrog txoj kev muaj.
Piv txwv li, kev rho tawm ntawm toluene los ntawm paraffin tuaj yeem ua tiav hauv txoj kev rho tawm distillation. Qhov sib xyaw ntawm toluene thiab iso-octane muaj ze li qhov hnyav molecular. Yog li ntawd, kev sib cais ntawm toluene tawm ntawm qhov sib tov no nyuaj heev. Tab sis thaum phenol ntxiv rau qhov sib tov, qhov kub ntawm iso-octane nce. Qhov no ua rau nws yooj yim cais toluene los ntawm qhov sib tov.
Qhov txawv ntawm Azeotropic thiab Extractive Distillation yog dab tsi?
Azeotropic vs Extractive Distillation |
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| Azeotropic distillation yog cov txheej txheem sib cais siv los cais cov khoom sib xyaw los ntawm kev tsim cov azeotrope. | Extractive distillation yog txheej txheem kev sib cais uas suav nrog qhov sib ntxiv ntawm qhov thib peb rau kev sib xyaw binary kom tso cai rau kev sib cais ntawm ob lub ntsiab lus. |
| Technique | |
| Hauv azeotropic distillation txheej txheem, tsim ntawm azeotrope ua ntej distillation yog ib qho tseem ceeb. | Nyob rau hauv cov txheej txheem extractive distillation, ib qho tsis-volatile tivthaiv yog ntxiv rau qhov sib tov uas tuaj yeem cuam tshuam qhov volatility ntawm cov khoom sib xyaw. |
| Kev sib cais | |
| Azeotropic distillation cais ib feem rau hauv lub vapor theem uas muaj tib yam tshuaj muaj pes tsawg leeg xws li nyob rau hauv cov kua theem. | Extractive distillation cais ib feem ntawm cov khoom siv matrix. |
Summary – Azeotropic vs Extractive Distillation
Distillation yog cov txheej txheem tshuaj siv rau kev sib cais ntawm cov khoom sib txawv hauv kev sib tov. Muaj ntau ntau hom kev distillation, yooj yim distillation yog hom yooj yim tshaj plaws. Azeotropic distillation thiab extractive distillation yog ob yam tseem ceeb ntawm distillation. Qhov txawv ntawm azeotropic thiab extractive distillation yog qhov tsim ntawm azeotrope yuav tsum tau cais cov khoom ntawm cov sib tov whereas, nyob rau hauv extractive distillation, tsis muaj azeotrope tsim tshwm sim.
