Qhov sib txawv tseem ceeb ntawm zeolite thiab MOF yog tias zeolite yog qhov tseem ceeb los ua cov catalyst, whereas MOF yog qhov zoo tagnrho rau kev txhawb nqa cov qauv rau catalysis lossis tuaj yeem ua tus catalyst.
Peb tuaj yeem txheeb xyuas zeolite thiab hlau cov qauv organic lossis MOFs ua ob yam khoom ntxeem tau uas muaj qhov pores tsawg dua 1 nanometers (xws li zeolite) lossis loj dua 1 nanometer (raws li hauv MOFs), feem.
YZeolite yog dab tsi?
Zeolite yog microporous aluminosilicate ntxhia. Nws yog tsuas yog pab tau raws li ib tug catalyst. Nyob rau hauv kev lag luam nplai, nws muaj txiaj ntsig zoo li adsorbent. Lub sij hawm no tau los rau hauv koob meej hauv 1756 tom qab kev tshawb fawb ntawm Swedish mineralogist Axel Fredrik Cronstedt. Nws tau soj ntsuam kev tsim cov pa ntau ntawm cov dej (uas tshwm sim hauv cov khoom siv los ntawm adsorption) thaum cua kub ceev ntawm ib qho khoom uas muaj stilbite. Raws li qhov kev soj ntsuam no, tus kws tshawb fawb no hu ua cov khoom siv zeolite, uas muaj lub ntsiab lus Greek, "zeo"="to boil", thiab "lithos"="stone".
Daim duab 01: Thomsonite - Ib Daim Ntawv Zeolite Mineral
Zeolite Structure
Nws muaj cov qauv ntxeem tau hauv zeolite uas tuaj yeem koom nrog ntau yam cations, suav nrog Na+, K+, Ca2+ thiab Mg2+. Cov no yog cov ions zoo uas tuaj yeem tuav tau xoob. Yog li, cov ions no tuaj yeem hloov pauv rau lwm cov ions thaum sib cuag nrog kev daws teeb meem. Cov tswv cuab hauv pob zeb hauv pawg zeolite suav nrog analcime, chabazite, clinoptilolite, stilbite, thiab lwm yam.
Daim duab 02: Microscopic Structure ntawm Zeolite
Thaum xav txog cov khoom ntawm zeolite, cov ntaub ntawv tshwm sim tuaj yeem cuam tshuam nrog cov dej hauv av alkaline. Ntxiv mus, cov ntaub ntawv no tuaj yeem tau crystallized nyob rau hauv ib puag ncig tom qab depositional ntau lub sijhawm. Tsis tas li ntawd, cov ntaub ntawv zeolite ntuj tsis tshua muaj tshwm sim hauv lub xeev ntshiab. Lawv feem ntau kis nrog lwm yam minerals, hlau, quartz, thiab lwm yam.
MOF yog dab tsi?
Metal-organic moj khaum lossis MOFs yog cov khoom sib xyaw ua ke uas muaj cov organic thiab inorganic pawg. Peb tuaj yeem soj ntsuam cov qauv ntawm cov ntaub ntawv no raws li crystalline thiab 3D hauv qhov xwm txheej, thiab nws tuaj yeem siv kev sib xyaw ua ke ntawm cov pawg tsis muaj zog xws li cov hlau ions lossis cov hlau nplaum nrog rau cov organic linker ligands. Qhov kev siv ntawm ob pawg nruj thiab hloov tau yooj yim tuaj yeem ua rau MOFs kom tau txais qhov ntev-ntev tunable pores, uas tuaj yeem koom nrog ntau yam ntawm cov molecules. Cov khoom no tuaj yeem raug kho kom zoo, uas tso cai rau lawv xaiv rau hom molecules uas tuaj yeem nkag mus rau hauv lawv qhov pores.
MOF Structure
Thaum xav txog cov qauv ntawm MOFs ze, peb tuaj yeem soj ntsuam cov pawg inorganic thiab organic tau npaj rau hauv ib txoj kev tshwj xeeb ua rau lub qhov hws. Cov qauv ntawm MOFs tshwm sim raws li kev sib koom tes sib koom tes ntawm inorganic nodes. Cov nodes zoo li tsim cov ces kaum ntawm cov pores muab, geometrical stability nrog rau cov qauv tsis tu ncua. Ntxiv mus, cov organic linkers uas txuas cov nodes ua ke muab hluavtaws versatility thiab modular functionality. Tsis tas li ntawd, peb tuaj yeem pom cov qauv qub yog rov ua dua hauv 3D qauv ntawm MOFs.
Qhov txawv ntawm Zeolite thiab MOF yog dab tsi?
Txawm hais tias zeolite yog qhov kev xaiv ua cov khoom ntxeem tau ntau xyoo, kev txhim kho ntawm lwm cov ntaub ntawv xws li hlau-organic moj khaum (MOF) thiab covalent organic moj khaum (COF) tau tawm tsam nws siv tam sim no. Qhov sib txawv tseem ceeb ntawm zeolite thiab MOF yog tias zeolite feem ntau muaj txiaj ntsig zoo li cov khoom siv hluav taws xob thaum MOF yog qhov zoo tagnrho rau cov qauv kev txhawb nqa rau catalysis, lossis lawv tuaj yeem ua raws li catalysts lawv tus kheej. Ntxiv mus, qhov pores hauv zeolite tsawg dua 1 nanometer, qhov pores hauv MOF loj dua 1 nanometer.
Cov infographic hauv qab no qhia txog qhov sib txawv ntawm zeolite thiab MOF hauv daim ntawv tabular.
Summary – Zeolite vs MOF
Peb tuaj yeem txheeb xyuas zeolite thiab hlau cov qauv organic lossis MOFs ua ob yam khoom ntxeem tau uas muaj qhov pores tsawg dua 1 nanometers (xws li zeolite) lossis loj dua 1 nanometer (raws li hauv MOFs), feem. Qhov sib txawv tseem ceeb ntawm zeolite thiab MOF yog tias zeolite feem ntau muaj txiaj ntsig zoo li cov khoom siv hluav taws xob thaum MOF yog qhov zoo tagnrho rau cov qauv kev txhawb nqa rau catalysis lossis lawv tuaj yeem ua raws li catalysts lawv tus kheej.
