selective production of light olefins from methanol over desilicated highly siliceous zsm-5 nanocatalysts

Highly siliceous zsm-5 nanocatalysts can dehydrate methanol to a wide range of hydrocarbons. in this study, the development of hierarchical h-zsm-5 nanocatalysts (si/al=200) were reported for the methanol-toolefins (mto) reaction. the nanocatalysts were prepared through a hydrothermal technique and treated by naoh desilication. the parent and desilicated nanocatalysts were characterized using fe-sem, xrd, ftir, nh3-tpd and n2 adsorption-desorption techniques. the mesoporosity increased five times without significant collapse of the crystalline framework as a result of the appropriate desilication of h-zsm-5 nanocatalyst. for the nanocatalyst, a high surface area of 189.5 m2 g-1, mesopore volume of 0.35 cm3 g-1 and well-adjusted strong acidity of 0.16 mmol nh3 g-1 resulted in a high methanol conversion of 100%, high propylene selectivity of 43% and low light paraffins selectivity of <8% in the mto reaction. a broad mesopore size of 2-10 nm suppressed coke deposition and provided a long catalytic life time of 75 h. the developed high silica nanocatalyst showed a high potential for industrial applications due to its stable performance.