F:Flammable;700-12-9Relevant articles and documents
Direct observation of hexamethylbenzenium radical cations generated during zeolite methanol-to-olefin catalysis: An ESR study
Kim, Sun Jung,Jang, Hoi-Gu,Lee, Jun Kyu,Min, Hyung-Ki,Hong, Suk Bong,Seo, Gon
, p. 9498 - 9500 (2011)
The generation of hexamethylbenzenium radical cations as the key reaction intermediate in chabazite-type molecular sieve acids (i.e., H-SAPO-34 and H-SSZ-13) during the methanol-to-olefin process has been directly evidenced by ESR spectroscopy.
Coupling of Methanol and Carbon Monoxide over H-ZSM-5 to Form Aromatics
Chen, Zhiyang,Ni, Youming,Zhi, Yuchun,Wen, Fuli,Zhou, Ziqiao,Wei, Yingxu,Zhu, Wenliang,Liu, Zhongmin
supporting information, p. 12549 - 12553 (2018/09/11)
The conversion of methanol into aromatics over unmodified H-ZSM-5 zeolite is generally not high because the hydrogen transfer reaction results in alkane formation. Now circa 80 % aromatics selectivity for the coupling reaction of methanol and carbon monoxide over H-ZSM-5 is reported. Carbonyl compounds and methyl-2-cyclopenten-1-ones (MCPOs), which were detected in the products and catalysts, respectively, are considered as intermediates. The latter species can be synthesized from the former species and olefins. 13C isotope tracing and 13C liquid-state NMR results confirmed that the carbon atoms of CO molecules were incorporated into MCPOs and aromatic rings. A new aromatization mechanism that involves the formation of the above intermediates and co-occurs with a dramatically decreased hydrogen transfer reaction is proposed. A portion of the carbons in CO molecules are incorporated into aromatic, which is of great significance for industrial applications.
K-promoted Mo/Co- and Mo/Ni-catalyzed Fischer-Tropsch synthesis of aromatic hydrocarbons with and without a Cu water gas shift catalyst
Wijayapala, Rangana,Yu, Fei,Pittman Jr., Charles U.,Mlsna, Todd E.
, p. 93 - 99 (2014/06/09)
The catalyst systems Mo/Co/K/ZSM-5 and Mo/Ni/K/ZSM-5, alone and with the added copper-based water gas shift catalyst, were used for the conversion of two CO/H2 ratios in a batch reactor. GC analysis of the gas phase was used to determine CO conversion while GCMS and NMR studies were used to characterize the liquid products formed and liquid product selectivities. The liquids were hydrocarbons consisting mainly of alkyl substituted benzenes. Methyl substitution in the alkyl benzenes in the product liquid ranged from an average of 1.3 to 4.5 methyls per ring depending on reaction conditions and reactant gas mole ratios. The additional presence of the WGS catalyst significantly increased CO conversion in the reactions taking place at 280 °C from ～25% to ～90% while increasing selectivity toward higher average methyl substitution. Similar conversions and selectivities were observed with both a bio-syngas and a 50/50 mixture of H2 and CO.
Direct observation of cyclic carbenium ions and their role in the catalytic cycle of the methanol-to-olefin reaction over chabazite zeolites
Xu, Shutao,Zheng, Anmin,Wei, Yingxu,Chen, Jingrun,Li, Jinzhe,Chu, Yueying,Zhang, Mozhi,Wang, Quanyi,Zhou, You,Wang, Jinbang,Deng, Feng,Liu, Zhongmin
supporting information, p. 11564 - 11568 (2013/11/06)
Carbenium ions in zeolites: Two important carbenium ions have been observed for the first time under working conditions of the methanol-to-olefins (MTO) reaction over chabazite zeolites using 13C NMR spectroscopy. Their crucial roles in the MTO
