Insight into the Dual Cycle Mechanism of Methanol-to-Olefins Reaction over SAPO-34 Molecular Sieve b

• 作 者: YU Bowen LOU Caiyi ZHANG Wenna XU Shutao HAN Jingfeng YU Zhengxi WEI Yingxu LIU Zhongmin
• 机 构: National Engineering Laboratory for Methanol to Olefins, Dalian National Laboratory for Clean Energy
• 出 处: 高等学校化学研究（英文版）
• 发表日期: 2020年6期
• 关键词: SAPO-34 Methanol-to-olefin(MTO) Polymethylbenzene Dual-cycle mechanism Isotopic

Methanol-to-olefins(MTO)reaction is one of the important non-petroleum routes to produce light olefins over acidic molecular sieves.In this study,the complete reaction course of MTO on SAPO-34 molecular sieve with retained organics evolution from induction period to deactivation period was investigated systematically at different weight hourly space velocities(WHSV)of methanol.By the aid of 12C/13C-methanol isotopic switch experiment,the dual cycle mechanism involving aromatics-based cycle and alkenes-based cycle was evaluated during the whole reac-tion process.The detailed reaction route varied with the evolution of the retained organics in the catalyst at different reaction stages.The aromatics-based cycle and alkenes-based cycle alternately dominate the reaction process.In the efficient reaction period,aromatics-based cycle is the main reaction mechanism,while in the induction and deactiva-tion periods,the contribution of alkenes-based cycle mechanism will become more important.