Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts

Razdan, Neil K.; Kumar, Anurag; Foley, Brandon L.; Bhan, Aditya

doi:10.1016/j.jcat.2019.11.004

Title: Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts

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Abstract

Acetylene is identified as a key intermediate in methane dehydroaromatization (DHA) reactions present in concentrations O(1) Pascal. The rank of acetylene and other C₂ hydrocarbon intermediates is determined by conversion-selectivity profiles collected from 0.01-8% methane conversion varied by extent of “non-selective” deactivation of Mo/H-ZSM-5 catalysts. Ethane is shown to be the sole primary product of methane pyrolysis and is sequentially dehydrogenated to ethylene and acetylene – which aromatizes to benzene with rates similar to direct acetylene aromatization measured in the absence of methane. The influence of C-H cleavage and C-C coupling events to control the rate and reversibility of DHA is assessed by the degree of reversibility control, introduced here for the first time, and the degree of rate control. Here, the approach to equilibrium of the methane to benzene synthesis reaction is length averaged and affinity averaged by the degree of reversibility control of each intervening elementary step to rigorously calculate forward rates of benzene synthesis by use of De Donder relations. Forward rates are found to be invariant along the catalyst bed once the DHA network reaches a pseudo-steady state and methane, ethane, and ethylene form an equilibrated pool.

Authors:

Razdan, Neil K. ^[1]; Kumar, Anurag ^[1]; Foley, Brandon L. ^[1];

^[1]

University of Minnesota, Twin Cities, Minneapolis, MN (United States)

Publication Date:: Wed Nov 27 00:00:00 EST 2019

Research Org.:: Univ. of Minnesota, Minneapolis, MN (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; USDOE

OSTI Identifier:: 1658229

Alternate Identifier(s):: OSTI ID: 1575967

Grant/Contract Number:: SC0019028; SC00019028

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Catalysis

Additional Journal Information:: Journal Volume: 381; Journal ID: ISSN 0021-9517

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 03 NATURAL GAS; Dehydroaromatization; Methane conversion; De Donder relations; Microscopic reversibility; Degree of rate control; Degree of reversibility control; H-ZSM-5; Molybdenum carbide

Citation Formats


                    Razdan, Neil K., Kumar, Anurag, Foley, Brandon L., and Bhan, Aditya. Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts.  United States: N. p., 2019. 
Web.  doi:10.1016/j.jcat.2019.11.004.

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                    Razdan, Neil K., Kumar, Anurag, Foley, Brandon L., & Bhan, Aditya. Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts.  United States.  https://doi.org/10.1016/j.jcat.2019.11.004

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                    Razdan, Neil K., Kumar, Anurag, Foley, Brandon L., and Bhan, Aditya. Wed .  
"Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts".  United States.  https://doi.org/10.1016/j.jcat.2019.11.004.  https://www.osti.gov/servlets/purl/1658229.

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@article{osti_1658229,

  title        = {Influence of ethylene and acetylene on the rate and reversibility of methane dehydroaromatization on Mo/H-ZSM-5 catalysts},

  author       = {Razdan, Neil K. and Kumar, Anurag and Foley, Brandon L. and Bhan, Aditya},

  abstractNote = {Acetylene is identified as a key intermediate in methane dehydroaromatization (DHA) reactions present in concentrations O(1) Pascal. The rank of acetylene and other C2 hydrocarbon intermediates is determined by conversion-selectivity profiles collected from 0.01-8% methane conversion varied by extent of “non-selective” deactivation of Mo/H-ZSM-5 catalysts. Ethane is shown to be the sole primary product of methane pyrolysis and is sequentially dehydrogenated to ethylene and acetylene – which aromatizes to benzene with rates similar to direct acetylene aromatization measured in the absence of methane. The influence of C-H cleavage and C-C coupling events to control the rate and reversibility of DHA is assessed by the degree of reversibility control, introduced here for the first time, and the degree of rate control. Here, the approach to equilibrium of the methane to benzene synthesis reaction is length averaged and affinity averaged by the degree of reversibility control of each intervening elementary step to rigorously calculate forward rates of benzene synthesis by use of De Donder relations. Forward rates are found to be invariant along the catalyst bed once the DHA network reaches a pseudo-steady state and methane, ethane, and ethylene form an equilibrated pool.},

  doi          = {10.1016/j.jcat.2019.11.004},

  journal      = {Journal of Catalysis},

  number       = ,

  volume       = 381,

  place        = {United States},

  year         = {Wed Nov 27 00:00:00 EST 2019},

  month        = {Wed Nov 27 00:00:00 EST 2019}

}

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