Mechanism of Decomposition of Surface Ethoxy Species to Ethene and Acidic OH Groups on H-ZSM-5

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• 作者：Junko N. Kondo ; Hiroshi Yamazaki ; Ryota Osuga ; Toshiyuki Yokoi ; Takashi Tatsumi
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2015
• 出版时间：June 18, 2015
• 年：2015
• 卷：6
• 期：12
• 页码：2243-2246
• 全文大小：256K
• ISSN：1948-7185

文摘

The reaction mechanism of the decomposition of ethoxy species to ethene and acidic OH groups on H-ZSM-5 was studied by IR spectroscopy using isotope-labeled ethanol. The concerted mechanism occurring on both the ethoxy (acid) site and the counterpart lattice oxygen was suggested by GC-MS analysis of evolved d₂-ethene and IR observation of the recovery of OH s groups on acid sites from the decomposition of CH₃CD₂O鈥?ethoxy species. The concerted mechanism was further confirmed by the estimation of activation energy for decomposition of CH₃CH₂O鈥? CH₃CD₂O鈥? and CD₃CD₂O鈥?ethoxy species, 122 卤 3, 125 卤 3, and 140 卤 5 kJ mol^鈥?, respectively, where the kinetic isotope effect was observed for the cleavage of the CH or CD bond of the methyl group of the ethoxy species.