1. Tshuaj lom los ntawm impurities ua rau Irreversible Deactivation
Kev ua haujlwm catalytic yog nyob ntawm ntau qhov chaw nquag ntawm cov catalyst nto. Hauv kev tsim khoom, cov khoom siv raw inevitably muaj cov kab mob tsis zoo xws li sulfur, phosphorus thiab hlau hnyav. Cov impurities no zoo li adsorb ntawm cov chaw ua haujlwm, tuav cov chaw tshuaj tiv thaiv thiab kev sib txuas nrog cov khoom nquag, yog li ua rau kev puas tsuaj mus tas li. Catalyst lom yog feem ntau irreversible. Nrog rau kev ua haujlwm ntev - lub sijhawm ua haujlwm, tus naj npawb ntawm cov chaw ua haujlwm tau zoo maj mam txo qis, ua rau kev ua haujlwm tsis tu ncua thiab qhov kawg ua tsis tiav ntawm cov catalyst.
2. Nto Carbon Deposition Blocking Micropores
Hauv cov txheej txheem catalytic zoo li roj av refining thiab cov organic synthesis, cov kev cuam tshuam sab xws li tawg thiab polymerization tshwm sim nrog cov tshuaj tiv thaiv tseem ceeb, tsim cov carbonaceous deposits. Cov deposits sib sau rau ntawm lub catalyst nto thiab sab hauv micropores, npog cov chaw nquag thiab thaiv cov pore raws, uas tiv thaiv cov reactants los ntawm kev tiv tauj cov catalyst. Lub teeb carbon deposition tuaj yeem raug tshem tawm ntawm qhov siab -kub calcination thiab rov tsim kho kom rov qab ua haujlwm catalytic. Txawm li cas los xij, hnyav thiab ntev - lub sij hawm deposition yuav ua rau cov pore blockage mus tas li, ua rau cov catalyst unrecyclable.
3.High - kub aging ua rau lub microstructure ntawm catalyst.
Feem ntau cov tshuaj tiv thaiv catalytic tshwm sim nyob rau hauv qhov kub thiab txias, uas yog ib qho tseem ceeb ntawm catalyst aging. Kev kub siab kub ua rau cov cab kuj sintering thiab pore vau. Thawj cov qauv ntxeem tau puas lawm, ua rau muaj kev poob qis hauv kev sib cuag zoo. Meanwhile, active grains ntawm catalyst nto agglomerate thiab loj hlob nrog txo dispersion, zoo heev txiav down muaj active chaw. Kev hloov pauv kub hnyav kuj tseem yuav ua rau muaj kev ntxhov siab ntawm cov qauv, ua rau tawg, pulverization thiab tev thiab rhuav tshem cov qauv catalyst.
4.Txoj kev ua haujlwm tsis ruaj khov ua kom nrawm hnav thiab kev ua haujlwm tsis zoo
Kev hloov pauv hauv kev ua haujlwm zoo heev ua rau cov catalyst deterioration. Variations nyob rau hauv lub zog siab thiab pub ntws tsis tu ncua cuam tshuam thiab scour catalyst hais, ua abrasion, fragmentation thiab pulverization, uas cuam tshuam qhov stability ntawm cov tshuaj tiv thaiv. Qhov chaw tsis ruaj khov tshaj plaws kuj ua rau muaj kev cuam tshuam ntau dua thiab ua rau cov pa roj carbon ntau ntxiv.
Nyob rau hauv kev tsim khoom, stabilizing kub, siab thiab pub tus nqi, raws li zoo raws li purifying raw cov ntaub ntawv nruj me ntsis, yog cov tseem ceeb ntsuas kom qeeb catalyst deactivation thiab ncua nws cov kev pab cuam lub neej.