Crystallization of SAPO Series Silicoaluminophosphate Zeolites and Effect of Their Composite Catalysts on CO Hydrogenation

Abstract

： The effects of mechanical stirring, ingredient composition and ciystallization parameters on hvclrothermal synthesis of S A P O - 3 4 and S A P O - 5 silicoaluminophosphate zeolites were investigated. The effects of granule-mixing process and powder-grinding process on the preparation of "silicoaluminophosphate zeolite/spiner' composite cata­ lysts were investigated. Compared with S A P O - 3 4 zeolite, S A P O - 5 zeolite ciystals exhibited stronger tolerance to m e ­ chanical action. X R D , physical adsorption, F E S E M and E D S were em])loyed to investigate the structure and tex-ture features of the materials. The catalytic performance of four composite catalysts for C O hydrogenation was c o m ­ pared. The sequence of phases which can make a composite catalyst more suppress C —— C coupling and produce more light hydrocaibons is ： S A P O - 3 4 > S A P O - 5 > tlZ n A l C ^ 0 4，， spinel phase. The sequence of phases that can mak e a composite catalyst have higher C O hydrogenation activity ( i.e., C O conversion) is: “ZnAlCi.04” spinel phase > S A P O - 3 4