Impact of temporal and spatial distribution of hydrocarbon pool on methanol conversion over H-ZSM-5
Impact of temporal and spatial distribution of hydrocarbon pool on methanol conversion over H-ZSM-5
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烃库时空分布对H-ZSM-5甲醇转化的影响
DOI：
10.1016/j.jcat.2017.08.003
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发表时间：
2017-10
影响因子：
7.3
通讯作者：
Deng F
中科院分区：
文献类型：
--
作者：
Wang;Chao;Sun;Xianyong;Xu;Jun;Qi;Guodong;Wang;Weiyu;Zhao;Xingling;Li;Wenzheng;Wang;Qiang;Deng;Feng;Wang Chao;Xu Jun;Qi Guodong;Wang Weiyu;Zhao Xingling;Li Wenzheng;Wang Qiang;Deng Feng;Sun Xianyong;Xu J;Deng F
通过固态核磁共振波谱和 GC-MS 研究了 H-ZSM-5 沸石上甲醇制烯烃 (MTO) 反应中的烃池 (HP) 物质。研究发现，碳正离子和甲苯 (MB) 等保留的 HP 物质的分布和反应性随着反应时间及其在催化剂床中的位置而变化。揭示了典型S形甲醇转化曲线的基本机制，其中主要反应路线取决于不同反应时间下不同HP物种的形成和反应性。在诱导期间，环戊烯基阳离子作为MBs的前体，表现出比后者更高的反应活性。烯烃的积累加速了反应，并通过随后的环戊烯基阳离子和芳族化合物的参与进一步增强，最终导致稳态反应。提出了基于烯烃、环戊烯基阳离子和MB的反应循环的相互转化来形成轻质烯烃。 MTO 反应中 HP 物质的共催化表明，环戊烯基阳离子和烯烃有利于丙烯的形成，而二甲苯和 triMB 等轻质 MB 则有利于乙烯的形成。在催化剂床内，环戊烯基阳离子和MB主要在上催化剂层中形成。实验表明，环戊烯基阳离子和烯烃在整个催化床中均保持高反应活性，而MBs仅在上部催化剂位置表现出高反应活性。
The hydrocarbon pool (HP) species in methanol-to-olefins (MTO) reactions over zeolite H-ZSM-5 were investigated by solid-state NMR spectroscopy and GC–MS. The distribution and reactivity of retained HP species such as carbocations and methylbenzenes (MBs) were found to evolve with reaction time and their positions in the catalyst bed. The underlying mechanism of the typical S-shaped methanol conversion curve was revealed, in which the dominating reaction route was found to be dependent on the formation and reactivity of different HP species that were varied at different reaction time. During the induction period, cyclopentenyl cations served as the precursor to MBs and exhibited higher reactivity than the latter. The reaction was accelerated by the accumulation of alkenes and further enhanced by consequent involvement of the cyclopentenyl cations and aromatics, which eventually led to a steady state reaction. The interconversions of the reaction cycles based on alkenes, cyclopentenyl cations, and MBs were proposed for the formation of light olefins. The co-catalysis of HP species in the MTO reactions showed that the cyclopentenyl cations and alkenes favored propene formation, while the light MBs such as xylene and triMB facilitated ethene formation. Within the catalyst bed, both cyclopentenyl cations and MBs were dominantly formed in the upper catalyst layers. The experiments indicated that both cyclopentenyl cations and alkenes maintained high reactivity throughout the catalytic bed, while MBs exhibited high reactivity only in the upper catalyst position.
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影响因子：
15
作者：
Patrick W. Goguen;Teng Xu;D. H. Barich;Timothy W. Skloss;Weiguo Song;Zhike Wang;J. Nicholas;J. F. Ha
通讯作者：
Patrick W. Goguen;Teng Xu;D. H. Barich;Timothy W. Skloss;Weiguo Song;Zhike Wang;J. Nicholas;J. F. Ha
DOI：
10.1002/chin.198334360
发表时间：
1983-04
期刊：
--
影响因子：
--
作者：
C. Chang
通讯作者：
C. Chang
影响因子：
3.6
作者：
Haw, JF;Marcus, DM
通讯作者：
Marcus, DM
影响因子：
7.3
作者：
Ilias, Samia;Bhan, Aditya
通讯作者：
Bhan, Aditya
影响因子：
15
作者：
N. Tajima;T. Tsuneda;and Fuminori Toyama;K. Hirao
通讯作者：
N. Tajima;T. Tsuneda;and Fuminori Toyama;K. Hirao