MASU SHAƘA MA'ADANAI, MASU TATARWA, DA MASU BUSHEWA
Sifefun ƙwayoyin halitta sune aluminosilicates na ƙarfe mai siffar crystalline waɗanda ke da hanyar sadarwa mai girma uku ta silica da alumina tetrahedra. Ana cire ruwan danshi na halitta daga wannan hanyar sadarwa ta hanyar dumama don samar da ramuka iri ɗaya waɗanda ke ɗaukar ƙwayoyin halitta na musamman.
Yawanci ana amfani da sieve mai kauri 4 zuwa 8 a aikace-aikacen gasphase, yayin da nau'in raga mai kauri 8 zuwa 12 ya zama ruwan dare a aikace-aikacen ruwa. Siffofin sieves na 3A, 4A, 5A da 13X sun dace da aikace-aikace na musamman.
An daɗe ana san su da ƙarfin bushewa (har zuwa digiri 90 na Celsius), ƙwayoyin cuta sun nuna amfani a cikin hanyoyin roba, suna ba da damar ware samfuran da ake so daga halayen danshi waɗanda galibi ke ƙarƙashin rashin daidaito. An nuna cewa waɗannan zeolites na roba suna cire ruwa, alcohols (gami da methanol da ethanol), da HCl daga tsarin kamar ketimine da enamine syntheses, ester condensations, da kuma canza aldehydes marasa cikawa zuwa polyenals.
| Nau'i | 3A |
| Tsarin aiki | 0.6 K2O: 0.40 Na2O: 1 Al2O3: 2.0 ± 0.1SiO2: x H2O |
| Bayani | Ana yin siffar 3A ta hanyar maye gurbin potassium cations don sodium ions na tsarin 4A, rage girman rami mai tasiri zuwa ~3Å, ban da diamita >3Å, misali, ethane. |
| Manyan Aikace-aikace | Rashin ruwa a cikin magudanan hydrocarbon marasa cikawa, gami da fashewar iskar gas, propylene, butadiene, acetylene; busar da ruwan polar kamar methanol da ethanol. Shakar kwayoyin halitta kamar NH3 da H2O daga kwararar N2/H2. An yi la'akari da shi azaman maganin busarwa na gabaɗaya a cikin kafofin polar da nonpolar. |
| Nau'i | 4A |
| Tsarin aiki | 1 Na2O: 1 Al2O3: 2.0 ± 0.1 SiO2: x H2O |
| Bayani | Wannan siffa ta sodium tana wakiltar nau'in A na sifefe na kwayoyin halitta. Buɗewar rami mai inganci shine 4Å, don haka ban da ƙwayoyin da ke da diamita mai inganci >4Å, misali, propane. |
| Manyan Aikace-aikace | An fi so a sha ruwa mai tsafta a cikin tsarin ruwa ko iskar gas da aka rufe, misali, a cikin marufi na magunguna, kayan lantarki da sinadarai masu lalacewa; cire ruwa a cikin tsarin bugawa da robobi da busar da kwararar hydrocarbon mai cike. Nau'ikan da aka shafa sun haɗa da SO2, CO2, H2S, C2H4, C2H6, da C3H6. Gabaɗaya ana ɗaukar su a matsayin maganin bushewa na duniya a cikin hanyoyin polar da nonpolar. |
| Nau'i | 5A |
| Tsarin aiki | 0.80 CaO : 0.20 Na2O : 1 Al2O3: 2.0 ± 0.1 SiO2: x H2O |
| Bayani | Ion calcium mai bambanci maimakon sodium cations suna ba da ramuka na ~5Å waɗanda ba su haɗa da ƙwayoyin da ke da diamita mai inganci >5Å ba, misali, duk zoben carbon 4, da mahaɗan iso. |
| Manyan Aikace-aikace | Raba paraffins na yau da kullun daga sarkar hydrocarbons masu rassa da kuma masu zagaye; cire H2S, CO2 da mercaptans daga iskar gas. Kwayoyin da aka haɗa sun haɗa da nC4H10, nC4H9OH, C3H8 zuwa C22H46, da dichlorodifluoro-methane (Freon 12®). |
| Nau'i | 13X |
| Tsarin aiki | 1 Na2O: 1 Al2O3: 2.8 ± 0.2 SiO2: xH2O |
| Bayani | Siffar sodium tana wakiltar tsarin asali na dangin nau'in X, tare da ingantaccen buɗewar rami a cikin kewayon 910¼. Misali, ba zai sha (C4F9)3N ba. |
| Manyan Aikace-aikace | Busar da iskar gas ta kasuwanci, tsarkake abinci daga iska a cikin shuka (cire H2O da CO2 a lokaci guda) da kuma ƙara ɗanɗanon hydrocarbon/iskar gas (cire H2S da mercaptan). |
Lokacin Saƙo: Yuni-16-2023
