Preparation of hierarchical H-[B]-ZSM-5 zeolites by a desilication method as a highly selective catalyst for conversion of methanol to propylene

摘要: A hydrothermal route was exploited to prepare high-silica H-ZSM-5 as well H-[B]-ZSM-5 zeolites, and the boron-modified type then desilicated with alkaline treatment. The properties of catalysts were investigated by different techniques, catalytic performance evaluated in methanol propylene reaction. effects three critical desilication parameters, including alkali concentration, temperature, treatment time on selectivity mesopore volume. results characterizations evinced that incorporation B zeolite reduced total surface area pore volume sample increased external area. Furthermore, a significant increase weak acid site density for boron-containing specimen observed. Also, specimens underwent an increment, while micropore almost constant. As opposed catalyst, optimum catalyst exhibited higher (48.8 vs. 40.7%) light olefins (76.9 71.2%), ratio ethylene (5.66 4.15). had lifetime MTP reaction (867 h) microporous (498 h).