高浓度体系下水含量对ZSM-5的合成及甲醇制丙烯催化性能的影响

Effect of Water Content in High Concentration System on ZSM-5 Synthesis and Catalytic Performance of Methanol to Propylene

用水热晶化法在高浓度体系下合成ZSM-5,考察体系中水含量对合成的影响.用XRD、NH3-TPD、XRF、SEM、N2吸附-脱附和甲醇制丙烯催化性能(MTP)等方法对样品进行表征与评价.结果表明,随着合成体系中水含量的减少,合成样品的相对结晶度提高,形貌由小颗粒团聚体生长为规则的大颗粒,酸量提高的同时介孔数目减少,虽然目标产物的丙烯选择性略有降低,然而单程寿命明显提高.

ZSM -5 catalyst was synthesized by hydrothermal crystallization method in high concentration system, and the influence of water content in synthetic system on synthesis was investigated. The samples properties were characterized by XRD, NH3 TPD, XRF, SEM, N2 adsorption desorption, and methanol to propylene （MTP） catalytic performance was evaluated. The results show that the relative crystallinity of the synthesized sample increases with the decrease of water content in synthesis system, and catalyst morphology aggregate from small particles into regular large particle, and acid increase while mesoporous amount decrease. Sample d had a relatively better effect with significantly improved single pass life, while the propylene selectivity was slightly reduced.