Selective conversion of methanol to propylene over highly dealuminated mordenite: Al location and crystal morphology effects

The growing consumption of light olefins has stimulated intensive researches on methanol to olefin (MTO) process which possesses great advantages for coal conversion value-added chemicals in an environmentally benign way. catalysts commonly used MTO faces several challenges such as poor selectivity control, low hydrothermal stability and short lifetime. In the present study, we prepared a series mordenite zeolites with variable Al contents (Si/Al molar ratios 51?436) by sequential dealumination treatment air-calcination acid leaching. textural properties, acidity location before after have been systematically studied their effect especially propylene (MTP) performance was thoroughly investigated. Si/Al over 150 selectively catalyzed MTP pathway, providing high 63% propylene/ethylene ratio > 10. Compared low-silica MOR catalysts, highly dealuminated showed much higher longer lifetime, can be further enhanced via harsh pretreatment. Furthermore, lifetime related crystal size along c -axis. excellent is likely ascribed mesopores formed upon scarce sites located T shared 8-member ring (MR) side pockets 12-MR pore channels. high-silica >150) way, long ~130 h. 8-MR channels well weakened strength.