Hauv kev lag luam catalytic units rau roj av refining, natural gas purification thiab sulfur recovery, tshwj xeeb thaj chaw ua hauj lwm pab raws li ib tug tseem ceeb lub cev thiab tshuaj taw qhia rau kev ntsuam xyuas cov kev ua tau zoo ntawm catalysts. Nws ncaj qha tswj hwm catalytic conversion efficiency, raw khoom tuav lub peev xwm thiab cov khoom stability, thiab kuj yog ib tug tseem ceeb kev ntsuas parameter tshuaj xyuas los ntawm txawv teb chaws cov neeg muas zaub thaum xaiv khoom.
Lub cheeb tsam tshwj xeeb ntawm cov catalyst yog hais txog tag nrho cov sab hauv thiab sab nraud cheeb tsam ntawm ib chav tsev loj ntawm cov khoom siv catalytic, npog sab nrauv ntawm cov cab kuj thiab cov phab ntsa sab hauv ntawm micropores thiab mesopores. Cov khoom xyaw nquag sib xyaw ua ke nyob rau hauv cov txheej txheem pore, uas ua raws li cov chaw tseem ceeb rau cov tshuaj tiv thaiv catalytic.
Cov tshuaj tiv thaiv catalytic tshwm sim nyob rau hauv peb theem sib law liag: adsorption, tshuaj tiv thaiv thiab desorption, tag nrho cov uas vam khom rau thaj tsam txaus. Cov impurity molecules xws li hydrogen sulfide, organic sulfur, arsenic thiab mercury muaj nyob rau hauv pub roj ua ntej yuav tsum tau adsorbed mus rau active chaw ntawm catalyst nto. Kev tsis txaus ntawm thaj chaw tshwj xeeb ua rau muaj qhov tsis txaus ntawm qhov chaw muaj adsorption, ua rau muaj coob tus ntawm cov khoom noj molecules tsis tuaj yeem tiv tauj cov khoom nquag thiab ncaj qha txo qis impurity tshem tawm efficiency.
Cov cheeb tsam tshwj xeeb ua haujlwm nyob rau hauv tandem nrog pore qauv los ua ke cuam tshuam rau huab hwm coj diffusion efficiency. Cov catalysts uas muaj qhov tshwj xeeb saum npoo av feem ntau yog nruab nrog zoo -tsim hierarchical micropore thiab mesopore raws, tso cai rau cov kua dej nkag mus tob rau hauv cov catalyst pellets rau kev siv tag nrho ntawm cov khoom nquag. Cov catalysts uas tsis tshua muaj qhov tshwj xeeb ntawm thaj chaw feem ntau raug kev txom nyem los ntawm kev sib tsoo los yog thaiv cov pore channel, yog li cov tshuaj tiv thaiv tsuas yog tshwm sim rau sab nrauv ntawm cov pellets thaum cov khoom siv sab hauv tseem tsis tau siv, ua rau luv luv lub neej kev pab cuam ntawm catalysts.
Cov teeb meem tshwm sim thaum lub sijhawm ua haujlwm nrog rau cov pa roj carbon deposition, hnyav hlau lom thiab pulverization tshwm sim los ntawm dej vapor yuav txuas ntxiv thaiv cov micropores thiab ua rau irreversible poob ntawm tej thaj chaw saum npoo, uas yog ib qho ntawm cov hauv paus ntsiab lus ntawm gradual catalyst deactivation.
Txawm li cas los xij, ib qho chaw siab heev ntawm qhov chaw tsis yog ib txwm xav tau; nws yuav tsum tau sib phim nrog cov txheej txheem kev khiav hauj lwm sib xws. Rau siab -kub sulfur rov qab thiab hydrogenation units, catalysts nrog ultra- cheeb tsam tshwj xeeb yog ua rau cov cab kuj sintering thiab ceev micropore vau nyob rau hauv qhov kub thiab txias, uas nyob rau hauv lem accelerates kev degradation. Rau cov chav ua haujlwm ntawm qhov chaw siab tshaj plaws thiab cov nqi ntws siab, qhov muag tsis pom kev mus rau thaj chaw tshwj xeeb siab heev yuav ua rau muaj roj ntws tawm tsam thoob plaws lub txaj catalyst thiab nce lub zog tag nrho ntawm qhov chaw.
Hauv kev tsim khoom lag luam, cov txheej txheem tsim cov cab kuj raug hloov kho raws li qhov kub thiab txias, pub muaj pes tsawg leeg thiab qhov chaw nrawm kom ua tiav qhov zoo - sib luag thaj tsam thaj tsam tshwj xeeb, tawm tsam qhov sib npaug ntawm kev ua haujlwm catalytic, txhua yam muaj zog thiab thermal stability.
Nyob rau hauv xaus, ib tug tsim nyog tswj qhov chaw nto lays lub hauv paus rau ruaj khov catalytic efficiency. Thaum lub sijhawm kev yuav khoom thiab kev saib xyuas, kev tswj xyuas nruj tshaj cov plua plav, dej vapor thiab hnyav hlau impurities tuaj yeem ua rau cov pore blockage, ua kom ruaj khov rau thaj chaw tshwj xeeb ntawm cov catalysts thiab ua kom muaj txiaj ntsig ua haujlwm ntawm tag nrho chav huv huv.