Kev npaj ntawm -alumina carrier (kem roj poob)
Cov txheej txheem sol-gel suav nrog kev ua kom cov hlau tsis huv hauv hydrochloric acid lossis txhuas chloride tov kom tau cov pob tshab thiab tsis muaj xim txhuas. Tom qab ntawd, aluminium sol yog tov nrog ib tug tov ntawm hexamethylenetetramine, thiab cov tee dej yog tsim thiab gelled rau hauv spheres nyob rau hauv ib tug kub kub kem. Cov spheres tom qab ntawd raug rau kev laus, ntxuav, ziab, thiab calcination los tsim cov txhuas oxide. Lub -Al2O3 spheres uas tsim los ntawm txoj kev no yog tus cwj pwm los ntawm qhov tsawg ntom ntom, siab pore ntim, thiab lub zog zoo. Hauv kev tsim khoom, kev ntxuav ntawm spheres yog qhov yooj yim, thiab cov kauj ruam pom tau raug tshem tawm, ua kom yooj yim rau kev ua haujlwm tsis tu ncua.
1, Tswj Porosity: Cov txheej txheem sol-gel tso cai rau kev tswj xyuas meej txog kev tsim cov pores hauv cov khoom. Los ntawm kev kho qhov tsis xws li cov concentration ntawm precursors, hnyav muaj pes tsawg leeg, thiab ziab tej yam kev mob, nws muaj peev xwm txiav lub pore loj faib kom haum rau tej daim ntaub ntawv.
2, Loj Qhov Chaw: Cov txheej txheem sol-gel ua rau kev tsim cov khoom siv nrog thaj chaw siab. Kev tsim cov sol tso cai rau kev sib faib ntawm cov hlau precursors, uas ua rau cov qauv ntxeem tau zoo thaum gelation. Qhov chaw siab saum npoo no txhim kho cov khoom siv reactivity thiab adsorption muaj peev xwm, ua kom muaj txiaj ntsig zoo li kev txhawb nqa catalyst.
3.Thermal stability: Cov kev tswj kev sib xyaw ua ke hauv cov txheej txheem sol-gel tuaj yeem ua rau cov khoom siv thermally ruaj khov. Los ntawm kev ua tib zoo xaiv cov khoom ua ntej thiab kev ua haujlwm, nws muaj peev xwm txo qis qhov tsis xws luag thiab xyuas kom muaj kev ruaj khov oxide network, uas yog qhov tseem ceeb rau kev tswj xyuas cov qauv kev ntseeg siab ntawm qhov kub thiab txias.
4.Hydrolysis Resistance: Txoj kev sol-gel tso cai rau kev sib koom ua ke ntawm cov khoom siv ntxiv lossis kev hloov kho saum npoo los txhim kho cov khoom tiv thaiv hydrolysis. Los ntawm kev qhia qee cov pab pawg ua haujlwm lossis siv cov txheej txheem ziab kom qhuav, nws muaj peev xwm txo tau qhov cuam tshuam ntawm cov khoom rau dej vim kev puas tsuaj, ua rau nws tsim nyog rau kev siv hauv ib puag ncig aqueous.
5.Uiformity thiab Reproducibility: Cov txheej txheem sol-gel muaj kev tswj xyuas zoo tshaj qhov muaj pes tsawg leeg thiab cov qauv ntawm cov khoom tshwm sim. Qhov kev tswj no tso cai rau kev tsim cov kev txhawb nqa nrog cov khoom zoo ib yam, uas yog qhov tseem ceeb rau kev ua kom rov tsim dua tshiab hauv cov txheej txheem catalytic.
Tom qab ntawd, Gamma-alumina (-alumina carriers) (kem roj poob) tuaj yeem siv ua catalyst carrier (txhawb)