Verifying the mechanism of the ethene-to-propene conversion on zeolite H-SSZ-13
Verifying the mechanism of the ethene-to-propene conversion on zeolite H-SSZ-13
复制标题
验证 H-SSZ-13 沸石上乙烯转化为丙烯的机理
DOI：
10.1016/j.jcat.2014.03.006
复制
发表时间：
2014-05-01
影响因子：
7.3
通讯作者：
Hunger, Michael
中科院分区：
文献类型：
--
作者：
Dai, Weili;Sun, Xiaoming;Hunger, Michael
制备了几种具有相似n(Si)/n（Al）比（SAPO-34除外）和不同孔结构的微孔分子筛，并将其用作乙烯制丙烯（ETP）催化剂。由8环窗连接的茶巴石笼组成的H-SSZ-13分子筛对乙烯的吸附量最高，ETP转化活性最好。H-SSZ-13脱铝后Brensted酸位的减少导致催化剂在ETP反应中的寿命延长。采用原位FT-IR、UV/Vis、GC-MS、TGA和H-1 MAS NMR等方法研究了H-SSZ-13催化剂在ETP过程中的反应机理和失活行为。乙烯被迅速寡聚转化为萘基碳离子，在ETP反应中起重要作用。这些物质的积累导致了多环芳烃的形成，而多环芳烃会导致H-SSZ-13孔隙的完全堵塞，并导致催化剂失活。(c) 2014 Elsevier Inc.版权所有。
Several types of microporous molecular sieves with similar n(Si)/n(Al) ratios (except for SAPO-34) and different pore structures were prepared and applied as ethene-to-propene (ETP) catalysts. H-SSZ-13 zeolite consisting of chabazite cages connected via 8-ring windows possessed the highest adsorption capacity for ethene and exhibited the best activity in the ETP conversion. The decreasing amount of Brensted acid sites after dealumination of H-SSZ-13 caused a prolonged lifetime of the catalyst in the ETP reaction. The reaction mechanism and deactivation behavior of H-SSZ-13 catalysts during the ETP process were investigated by in situ FT-IR, UV/Vis, GC-MS, TGA and H-1 MAS NMR methods. Ethene was rapidly oligomerized and converted into naphthalene-based carbenium ions, playing a significant role in the ETP reaction. The accumulation of these species lead to the formation of polycyclic aromatics, which are responsible for a total blocking of H-SSZ-13 pores, and cause the deactivation of the catalyst. (c) 2014 Elsevier Inc. All rights reserved.