Stabilizing the framework of SAPO-34 zeolite toward long-term methanol-to-olefins conversion

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

doi:10.1038/s41467-021-24403-2

Stabilizing the framework of SAPO-34 zeolite toward long-term methanol-to-olefins conversion

Nat Commun. 2021 Aug 2;12(1):4661. doi: 10.1038/s41467-021-24403-2.

Authors

Liu Yang¹, Chang Wang¹, Lina Zhang¹, Weili Dai^{2

3}, Yueying Chu⁴, Jun Xu⁴, Guangjun Wu¹, Mingbin Gao⁵, Wenjuan Liu⁵, Zhaochao Xu⁵, Pengfei Wang⁶, Naijia Guan^{1

7}, Michael Dyballa⁸, Mao Ye⁵, Feng Deng⁴, Weibin Fan⁶, Landong Li^{1

7}

Affiliations

¹ School of Materials Science and Engineering, and National Institute for Advanced Materials, Nankai University, Tianjin, P.R. China.
² School of Materials Science and Engineering, and National Institute for Advanced Materials, Nankai University, Tianjin, P.R. China. weilidai@nankai.edu.cn.
³ Key Laboratory of Advanced Energy Materials Chemistry of the Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin, P.R. China. weilidai@nankai.edu.cn.
⁴ National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, P. R. China.
⁵ Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, P. R. China.
⁶ State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi, P. R. China.
⁷ Key Laboratory of Advanced Energy Materials Chemistry of the Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin, P.R. China.
⁸ Institute of Chemical Technology, University of Stuttgart, Stuttgart, Germany.

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 ²⁷Al, ³¹P MAS NMR, and 2D ³¹P-²⁷Al 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.