dual-templated synthesis of si-rich [b]-zsm-5 for high selective light olefins production from methanol

Methanol dehydration is a high potential route for the production of light olefins (c2-c4). in this study, hierarchical si-rich [b]-zsm-5 catalysts (si/al= 200) were prepared through one-pot hydrothermal synthesis, including boron as a promoter and ethanol as a low-cost secondary template. n2 adsorptiondesorption, xrd, fe-sem, and ft-ir techniques were applied to characterize the catalysts. the effect of different amounts of ethanol and different operating conditions was studied on the zsm-5 catalyst preparation and performance in methanol-to-olefins (mto) reaction. the results showed that the optimum amount of ethanol (ethanol/tpabr=5) led to the highest crystallinity (91.2%), the highest specific surface area (>400 m2g-1), and total pore volume (0.19 cm3g-1). the best catalytic performance was obtained at temperature of 480°c and methanol hourly space velocity (whsv) of 7.2 h-1. the optimum catalyst had the highest propylene selectivity (58%) and light olefin selectivity (85%). the results proved the high capability of the new strategy for the efficient and fast development of the mto catalyst.