Catalytic conversion of methane into benzene over ceria–zirconia‐promoted molybdenum‐supported zeolite for methane dehydroaromatization

Abstract

The promotional effect of mixed ceria–zirconia oxides (CZO) over the Mo/HZSM‐5 catalyst for methane dehydroaromatization (MDA) reaction was studied. The surface and structural properties of the synthesized catalyst were thoroughly exemplified using various microscopic and spectroscopic tools, and the correlation between catalytic properties and its performance for MDA reaction is discussed. The impregnation of CZO solid solution on Mo/HZSM‐5 was monitored to give an excellent catalytic performance and improved benzene production rate (4.5 μmol/gcat.s) related to the conventionally prepared Mo/HZSM‐5 (3.1 μmol/gcat.s) catalyst. In addition, a significant reduction in coke formation was examined in the CZO‐modified Mo/HZSM‐5 catalyst. The prevailing comprehension for higher catalytic activity could be because of the redox properties of CZO‐deposited Mo/HZSM‐5, which acts as a selective oxygen supplier and performs hydrogen combustion during the reaction, which is indirectly probed by residual gas analysis‐mass spectroscopy, oxygen‐temperature programmed desorption, and hydrogen‐temperature programmed reduction analysis. The selective hydrogen combustion prevents the over‐oxidation of aromatic species formed during the reaction, whereas the generated steam helps in reducing the coke content deposition in the MDA reaction. Thus, the advantage of CZO‐incorporated Mo/HZSM‐5 is manifested as it promotes the reaction equilibrium to shift towards the formation of benzene which is favourable for MDA reaction.

Recent Progress and Opportunity of Metal Single‐Atom Catalysts for Biomass Conversion Reactions

“…Overall, it can be said that the choice of support materials viz. metal oxides/layered oxides, [123] zeolites, [124] carbon-based materials, [125] can be critical depending on the specific requirements of the catalytic reaction. The properties of the metal atom in the SACs thus can be tailored depending on the choice of the support.…”

Enhanced catalytic performance for methane dehydro‐aromatization on Mo/HMCM‐49 prepared with citric acid

“…They are mainly produced through catalytic reforming and cracking reactions of the petroleum. [1,2] However, overexploitation of petroleum can lead to rapid depletion of resources. As a major component of natural gas, methane is abundant in reserves and relatively inexpensive compared to petroleum resources, but it is also the most stable organic molecule.…”