MeZrAPO-5 MOLECULAR SIEVES AS SOLID ACID CATALYSTS IN LINEAR ALKYLBENZENE SYNTHESIS I.Synthesis of the Catalyst and Its Affecting Factors

A series of zirconio-aluminophosphate molecular sieves(MeZrAPO-5) as solid acid catalysts in alkylation of benzene with linear olefins were synthesized by using the hydrothermal synthesis method. The MeZrAPO-5 molecular sieves have the same structure as AlPO 4-5 in which some P and Al atoms were isomorphously substituted by Zr and at least one of B,Si,Ga,Ge,Fe,Sn and Mg elements. The removal of template from molecular sieves and the effects of crystallization temperature, crystallization time, substituted atoms and three kinds of boehmite raw materials on the synthesis were investigated and discussed. The optimum conditions of crystallization as well as for template removal were proposed. The results showed that crystallization temperature higher than 150 ℃, n(TEA)/n(Al 2O 3)≥1.5 and the addition of Zr atoms were favorable to the formation of the MeZrAPO-5 crystal phase. The MeZrAPO-5 synthesized by using boehmites with small crystal size and high purity resulted in higher crystallinity.