Molecular sievesyog cov ntaub ntawv tseem ceeb rau roj thiab kua sib cais thiab purification hauv ntau yam lag luam. Lawv yog cov crystalline metalloaluminosilicates nrog cov pores sib xws uas xaiv adsorb molecules raws li lawv qhov loj thiab cov duab. Covmanufacturing txheej txheem ntawm molecular sieveskoom nrog ntau txoj hauv kev los xyuas kom meej tias cov khoom siv zoo nrog cov pore qhov ntau thiab tsawg thiab cov khoom.
Kev tsim cov molecular sieves pib nrog kev xaiv cov khoom siv raw, suav nrog sodium silicate, alumina thiab dej. Cov ntaub ntawv no tau muab sib xyaw rau hauv cov proportions meej los ua ib homogeneous gel, uas tom qab ntawd raug rau cov txheej txheem hydrothermal synthesis. Nyob rau hauv cov kauj ruam no, cov gel yog rhuab mus rau qhov kub thiab txias nyob rau hauv lub xub ntiag ntawm alkaline tshuaj los txhawb lub tsim ntawm ib tug crystal qauv nrog uniform pores.
Cov theem tseem ceeb tom ntej hauv cov txheej txheem tsim khoom yog kev sib pauv ion, uas suav nrog kev hloov cov sodium ions hauv cov qauv siv lead ua nrog lwm cov cations xws li calcium, potassium lossis magnesium. Cov txheej txheem ion pauv no yog qhov tseem ceeb rau kev tswj hwm kev ua haujlwm ntawm molecular sieves, nrog rau kev muaj peev xwm adsorption thiab kev xaiv. Hom cation siv rau kev sib pauv ion nyob ntawm qhov kev thov tshwj xeeb ntawm cov molecular sieve.
Tom qab ion pauv, cov molecular sieves undergo ib tug series ntawm ntxuav thiab ziab cov kauj ruam kom tshem tawm tej impurities thiab residual tshuaj los ntawm cov txheej txheem ntau lawm. Qhov no ua kom ntseeg tau tias cov khoom kawg ua tau raws li cov qauv purity nruj uas yuav tsum tau muaj rau cov ntawv thov kev lag luam. Tom qab kev ntxuav thiab ziab kom tiav, cov molecular sieves yog calcined ntawm qhov kub thiab txias kom stabilize cov qauv siv lead ua thiab tshem tawm cov organic tebchaw.
Cov kauj ruam kawg hauv kev tsim cov txheej txheem suav nrog kev ua kom cov molecular sieves los npaj lawv rau kev siv adsorption. Cov txheej txheem ua kom no feem ntau suav nrog cua sovmolecular sieventawm qhov kub thiab txias kom tshem tawm cov dej noo thiab txhim kho nws cov khoom adsorption. Lub sijhawm thiab qhov kub thiab txias ntawm cov txheej txheem ua kom zoo yog ua tib zoo tswj kom ua tiav qhov xav tau qhov pore loj thiab thaj chaw ntawm cov molecular sieve.
Molecular sieves muaj nyob rau hauv ntau qhov pore, suav nrog 3A, 4A thiab 5A, txhua qhov tsim nyog rau cov ntawv thov tshwj xeeb. Piv txwv li,3A molecular sievesfeem ntau yog siv rau lub cev qhuav dej ntawm cov pa roj thiab kua, thaum4A thiab 5A molecular sievesyog nyiam rau adsorbing loj molecules thiab tshem tawm impurities xws li dej thiab carbon dioxide.
Nyob rau hauv cov ntsiab lus, kev tsim cov molecular sieves yog ib tug complex thiab sophisticated txheej txheem uas muaj ob peb kauj ruam tseem ceeb, xws li hydrothermal synthesis, ion pauv, ntxuav, ziab, calcination, thiab ua kom. Cov kauj ruam no yog ua tib zoo tswj los tsimmolecular sievesnrog cov khoom customized thiab qhov pore qhov ntau thiab tsawg kom tau raws li cov kev xav tau ntau yam ntawm kev lag luam xws li petrochemical, tshuaj thiab kev ua lag luam ntuj. Siab zoomolecular sieves manufacturedlos ntawm cov tuam txhab muaj npe nrov ua lub luag haujlwm tseem ceeb hauv kev ua tiav cov txheej txheem sib cais thiab kev ua kom huv huv hauv ntau daim ntawv thov kev lag luam.
Lub sij hawm xa tuaj: Plaub Hlis-19-2024