Zeolite Molecular Sieve

Zeolite molecular sieve

Zeolite yog ib qho aluminosilicate tsim los ntawm AlO4 tetrahedra hloov SiO4 tetrahedra, ua rau cov nqi tsis zoo uas sib npaug los ntawm kev sib pauv cations nyob rau hauv lub pores thiab kab noj hniav thoob plaws hauv cov qauv. Feem ntau hais lus, CO2 ntes los ntawm zeolites nyob ntawm cov yam ntxwv xws li cov qauv thiab muaj pes tsawg leeg ntawm zeolite lub moj khaum, cations, thiab pab pawg ua haujlwm. Ntawm cov ntaub ntawv ntxeem tau rau kev sib cais CO2, zeolites tau txais koob meej hauv kev siv tshuab adsorption vim lawv qhov zoo xws li muaj qhov zoo, tus nqi qis, siab CO2 capture tus nqi, ceev kinetics, thiab zoo tshuaj thiab thermal stability.

Ntau yam kev siv. Kho cov qauv qauv, cations, tshuaj hloov kho thiab cov khoom siv sib xyaw yog suav tias yog txoj hauv kev zoo rau CO2 adsorption thiab desorption kev ua tau zoo ntawm cov zeolites siab. siv molecular simulation los simulate 13X
Cation pauv nrog sib txawv Li +, K + thiab Ca2+ cov ntsiab lus hauv zeolites. Lub adsorption kev ua tau zoo ntawm ntau yam cation txauv zeolites rau CO2 tau soj ntsuam los ntawm cov yam ntxwv ntawm qhov pore ntim, adsorption isotherm, adsorption tshav kub thiab CO2 / N2 selectivity. Nws tau pom tias CO2 molecule muaj lub sijhawm quadrupole. , uas tuaj yeem siv nrog cov cationic zeolites me me xws li Li +, qhov sib piv ntawm silicon-rau-aluminium kuj muaj qhov cuam tshuam loj rau kev xaiv adsorption ntawm CO2. Calleja et al. tshawb xyuas cov nyhuv ntawm Si / Al piv ntawm zeolite polarity thiab CO2 adsorption los ntawm kev kho cov zeolite Si / Al ratio. Nws pom tau tias raws li Si / Al piv txo qis, qhov kev xaiv ntawm adsorbent rau CO2 nce.

Cov khoom siv zeolite tsis pub khi nrog cov qauv hierarchical tau npaj siv 3D tshuab luam ntawv, uas pom tau tias muaj kev ruaj ntseg zoo heev thiab muaj peev xwm adsorption ntawm CO2 ntawm 245.52 mg / g nyob rau hauv qhov kub thiab txias. Ib yam khoom siv zeolite tau npaj rau ntawm 25 Lub tooj liab-doped RHO zeolite muaj CO2 peev xwm ntawm 3.2 mmol / g ntawm degree, ua rau nws muaj peev xwm ua kom muaj zog viav vias adsorption carbon capture technology. Kev hloov kho tshuaj muaj txiaj ntsig zoo txhim kho cov adsorption selectivity ntawm zeolite rau CO2. Monoethanolamine (MEA) thiab ethylenediamine (ED) yog tshuaj kho rau lub zeolite moj khaum los ntawm ionic bonds kom kov yeej cov teeb meem degradation ntawm amines. Cov qauv amine @ HY npaj tau zoo heev CO2 adsorption selectivity, thiab muaj lub voj voog zoo thermal stability nyob rau hauv cov xwm txheej ntawm adsorption kub ntawm 9 0 degree thiab desorption kub ntawm 150 degree . Amines xws li monoethanolamine, tetraethylpentbutylamine, thiab morpholine tau thauj khoom ntawm NaY zeolite. Cov txiaj ntsig kev tshawb fawb pom tau tias thaum lub siab ib txwm muaj thiab 323 K kub, kev sib cuam tshuam ntawm pawg amine nyob rau saum npoo ntawm NaY zeolite thiab CO2 yog lub luag haujlwm tseem ceeb ntawm nws cov adsorption. Piv nrog rau cov pa roj carbon activated, zeolite muaj peev xwm ntes tau zoo dua thiab siab dua CO2 / N2 selectivity hauv cov pa roj nrog qis CO2 ib nrab siab (15% CO2, 85% N2). Txawm li cas los xij, kuj tseem muaj qhov teeb meem ntawm kev txo qis hauv adsorption muaj peev xwm nyob rau hauv qhov kub thiab txias, thiab CO2 adsorption muaj peev xwm yog qhov tsis txaus siab tshaj 200 degree. Kev lag luam tawm ntawm lub peev xwm adsorption, adsorption kinetics thiab mechanical stability ntawm zeolites tseem yog ib qho kev sib tw loj hauv lawv cov ntawv thov kev lag luam. Z Pilot khiav kev xeem tau ua nyob rau hauv ib-theem VPSA chav tsev ntim nrog 5A zeolite thiab 13X zeolite. Rau kev ntes ntawm dehumidified flue gas nrog ib tug CO2 concentration ntawm 15.0%, 5A zeolite tuaj yeem ncav cuag ib qho kev nce ntxiv ntawm 71% mus rau 81%, thiab tus nqi rov qab yog 86% mus rau 91%; Txawm hais tias 13X zeolite muaj peev xwm ua tau zoo dua CO2 adsorption, tab sis tau pom qhov ua tau zoo sib xws rau 5A zeolite hauv kev sim ua haujlwm, nrog rau kev ua kom muaj zog ntxiv ntawm 73% mus rau 82% thiab rov qab tus nqi ntawm 85% mus rau 95%. Qhov laj thawj tseem ceeb yog qhov muaj zog polarity ntawm 13X ua rau desorption kim dua. Yog li ntawd, nyob rau hauv daim ntawv thov, kev xaiv ntawm zeolite yuav tsum tau raws li qhov tseeb pub roj tej yam kev mob thiab cov adsorption thiab desorption kinetic yam ntxwv ntawm lub zeolite.