Influences of the confinement effect and acid strength of zeolite on the mechanisms of Methanol-to-Olefins conversion over H-ZSM-5: A theoretical study of alkenes-based cycle

doi:10.1016/j.micromeso.2016.05.029

	Influences of the confinement effect and acid strength of zeolite on the mechanisms of Methanol-to-Olefins conversion over H-ZSM-5: A theoretical study of alkenes-based cycle
	Zhang, Wenna 2,3; Chu, Yueying 1; Wei, Yingxu 2; Yi, Xianfeng 1,3; Xu, Shutao 2; Huang, Jindou 2; Zhang, Mozhi 2,3; Zheng, Anmin 1; Deng, Feng 1; Liu, Zhongmin 2
刊名	MICROPOROUS AND MESOPOROUS MATERIALS
	2016-09-01
卷号	231 页码:216-229
关键词	Methanol-to-olefins Conversion Zeolite Catalysts Reaction Mechanism Confinement Effect Acid Strength Density Functional Theory
ISSN号	1387-1811
DOI	10.1016/j.micromeso.2016.05.029
文献子类	Article
英文摘要	Methanol-to-Olefins (MTO) conversion over acidic zeolite catalysts has become the most important non petrochemical route for the production of light olefins. The 'dual-cycle' mechanism (i.e., alkenes-based cycle and aromatics-based cycle) over H-ZSM-5 zeolite has been generally accepted for olefins generation from methanol conversion. However, the relationship between the catalytic performance and the confinement effect/acid strength of the catalyst is still unclear. Herein, the methylation, isomerization and cracking processes involved in the alkenes-based cycle are discussed in-depth by density functional theory (DFT) calculations. The calculation results predicted that the transition states can be considerably stabilized by the van der Waals (vdW) interactions from the zeolite framework, resulting in the reduction of the activation barriers. And acid strength can also enhance the reaction activities. However, the catalytic reactivity of all elementary steps in the alkenes-based cycle can be improved at a different degree with increasing the acid strength. In addition, the ethene formation, transformation and the precursor of ethene formation need higher energy. And increasing acid strength can sharply decrease the activation barriers of ethene formation of cracking reaction, indicating that ethene formation may need strong acid strength. (C) 2016 Elsevier Inc. All rights reserved.
WOS关键词	CATALYZED METHYLATION REACTIONS ; HYDROCARBON POOL MECHANISM ; CO-REACTION ; ISOMORPHOUS SUBSTITUTION ; SHAPE-SELECTIVITY ; DIMETHYL ETHER ; CARBENIUM IONS ; ZSM-5 ZEOLITE ; CRACKING ; KINETICS
WOS研究方向	Chemistry ; Science & Technology - Other Topics ; Materials Science
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000379705800024
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/170420]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
通讯作者	Zheng, Anmin; Liu, Zhongmin
作者单位	1.Chinese Acad Sci, Inst Phys & Math, Natl Ctr Magnet Resonance Wuhan, State Key Lab Magnet Resonance & Atom Mol Phys, Wuhan 430071, Peoples R China 2.Chinese Acad Sci, Dalian Inst Chem Phys, iChEM Collaborat Innovat Ctr Chem Energy Mat, Natl Engn Lab Methanol Olefins,Dalian Natl Lab Cl, Dalian 116023, Peoples R China 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Wenna,Chu, Yueying,Wei, Yingxu,et al. Influences of the confinement effect and acid strength of zeolite on the mechanisms of Methanol-to-Olefins conversion over H-ZSM-5: A theoretical study of alkenes-based cycle[J]. MICROPOROUS AND MESOPOROUS MATERIALS,2016,231:216-229.
APA	Zhang, Wenna.,Chu, Yueying.,Wei, Yingxu.,Yi, Xianfeng.,Xu, Shutao.,...&Liu, Zhongmin.(2016).Influences of the confinement effect and acid strength of zeolite on the mechanisms of Methanol-to-Olefins conversion over H-ZSM-5: A theoretical study of alkenes-based cycle.MICROPOROUS AND MESOPOROUS MATERIALS,231,216-229.
MLA	Zhang, Wenna,et al."Influences of the confinement effect and acid strength of zeolite on the mechanisms of Methanol-to-Olefins conversion over H-ZSM-5: A theoretical study of alkenes-based cycle".MICROPOROUS AND MESOPOROUS MATERIALS 231(2016):216-229.