A route to form initial hydrocarbon pool species in methanol conversion to olefins over zeolites
A route to form initial hydrocarbon pool species in methanol conversion to olefins over zeolites
复制标题
甲醇在沸石上转化为烯烃时形成初始烃库物质的途径
DOI：
10.1016/j.jcat.2014.05.015
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发表时间：
2014-08-01
影响因子：
7.3
通讯作者：
Fan, Weibin
中科院分区：
文献类型：
--
作者：
Li, Junfen;Wei, Zhihong;Fan, Weibin
甲醇在沸石催化剂上转化为烃类的过程中，初始C-C键的形成机理是一个巨大的挑战，尽管许多研究者已经做了大量的工作并取得了显著的进展。在这里，一个令人信服的路线形成的初始碳氢化合物池（HCP）的物种涉及原始的C-C键从二甲醚（DME）和/或甲醇结合一致的实验和理论计算结果说明。详细的实验结果为SAPO-34催化甲醇制烯烃的直接反应机理提供了有力的证据。通过甲氧基与DME的反应，检测到了一个关键中间体甲氧基甲基阳离子，并从理论上得到了验证。该中间体物质随后与DME或甲醇反应以产生含C-C键的化合物1，2-二甲氧基乙烷或2-甲氧基乙醇。氧鎓阳离子的进一步形成导致醚或醇的生成，并进一步导致丙烯作为诱导HCP机制发生的主要烯烃产物。(c)2014爱思唯尔公司All rights reserved.
The formation mechanism of the original C-C bond in methanol conversion to hydrocarbons over zeolite catalysts remains a grand challenge, although many researchers have done a lot of work and made significant progress. Here, a convincing route for formation of initial hydrocarbon pool (HCP) species involving original C-C bonds from dimethyl ether (DME) and/or methanol is illustrated by combining coincident experimental and theoretically calculated results. Elaborate experimental results gave strong evidence for predominant direct mechanism in the initial methanol-to-olefins process catalyzed by SAPO-34. A critical intermediate of the methoxymethyl cation was detected and theoretically verified through the reaction of the methoxy group and DME. This intermediate species subsequently reacted with DME or methanol to produce C-C bond-containing compounds 1,2-dimethoxyethane or 2-methoxyethanol. Further formation of oxonium cations led to generation of ethers or alcohols, and further to propene as the primary alkene product that induced the occurrence of the HCP mechanism. (c) 2014 Elsevier Inc. All rights reserved.