论文题目:Stabilizing the framework of SAPO-34 zeolite toward long-term methanol-to-olefins conversion
论文作者:Liu Yang, Chang Wang, Lina Zhang, Weili Dai*, Yueying Chu, Jun Xu, Guangjun Wu, Mingbin Gao, Wenjuan Liu, Zhaochao Xu, Pengfei Wang, Naijia Guan, Michael Dyballa, Mao Ye, Feng Deng, Weibin Fan, Landong Li
Abstract:
As a commercial MTO catalyst, SAPO-34 zeolite exhibits excellent recyclability probably due to its intrinsic good hydrothermal stability. However, the structural dynamic changes of SAPO-34 catalyst induced by hydrocarbon pool (HP) species and the water formed during the MTO conversion as well as its long-term stability after continuous regenerations are rarely investigated and poorly understood. Herein, the dynamic changes of SAPO-34 framework during the MTO conversion were identified by 1D Al-27, P-31 MAS NMR, and 2D P-31-Al-27 HETCOR NMR spectroscopy. The breakage of T-O-T bonds in SAPO-34 catalyst during long-term continuous regenerations in the MTO conversion could be efficiently suppressed by pre-coking. The combination of catalyst pre-coking and water co-feeding is established to be an efficient strategy to promote the catalytic efficiency and long-term stability of SAPO-34 catalysts in the commercial MTO processes, also sheds light on the development of other high stable zeolite catalyst in the commercial catalysis. Stability of zeolite catalysts is a highly desirable property for commercial methanol to olefins conversion but extremely challenging to achieve. Here, the authors combine the catalyst pre-coking and water co-feeding to develop an efficient strategy to enhance the long-term stability of SAPO-34 catalyst.