磷改性ZSM-5/磷酸铝复合分子筛在甲醇制丙烯反应中的应用

以磷酸二氢铵对ZSM-5/磷酸铝 (ZSM-5/AlPO₄-m) 复合分子筛进行P改性，得到wP-ZSM-5/AlPO₄-m催化剂，采用XRD、N₂吸附-脱附、NH₃-TPD和FT-IR表征其物化性能，并系统地考察了在甲醇制丙烯(MTP)反应中，wP-ZSM-5/AlPO₄-m中P质量分数，反应温度、空速(MHSV)等反应条件对该复合分子筛催化性能的影响。结果表明，P改性可以有效地调节ZSM-5/AlPO₄-m的比表面积及酸性分布，3%P-ZSM-5/AlPO₄-m催化剂中B酸与L酸中心数的最大比达到3.03。当反应温度为500℃、MHSV为1 h-^-1时，3%P-ZSM-5/AlPO₄-m催化剂表现出最佳的MTP活性和稳定性；反应持续73 h，甲醇转化率保持100%，丙烯的单程选择性和产物中丙烯/乙烯摩尔比分别保持在50.0%和5。

Application of Phosphorus Modified ZSM-5/Aluminophosphates Composite Zeolite in Methanol to Propylene Reaction

P modified ZSM-5/aluminophosphates composite zeolite (w-P-ZSM-5/AlPO₄-m) was obtained by NH₄ H₂ PO₄ modification of ZSM-5/AlPO₄-m and characterized by XRD, N₂ adsorption-desorption, NH₃-TPD, FT-IR and so on. The effects of P loaded amount in wP-ZSM-5/AlPO₄-m and the reaction conditions, reaction temperature and space velocity, on methanol conversion and product selectivity of MTP were investigated. It was confirmed that the surface area, acid strength and acid amount of wP-ZSM-5/AlPO₄-m were effectively regulated by P modification, and the maximum ratio of B acid and L acid reached 3.03 in 3%P-ZSM-5/AlPO₄-m, which had the best catalytic activity and stability at the reaction temperature of 500℃ and MHSV of 1 h^-1. The conversion rate of methanol, selectivity of propylene, molar ratio of propylene and ethylene remained around 100%, 50% and 5, respectively, when the reaction continued for 73 h.