Catalytic Conversion of Methane: Carbon Dioxide Reforming and Oxidative Coupling

Abstract

Natural gas conversion remains one of the essential technologies for current energy needs. This review focuses on the mechanistic aspects of the development of efficient and durable catalysts for two reactions, carbon dioxide reforming and the oxidative coupling of methane. These two reactions have tremendous technological significance for practical application in industry. An understanding of the fundamental aspects and reaction mechanisms of the catalytic reactions reviewed in this study would support the design of industrial catalysts. CO2 reforming of methane utilizes CO2, which is often stored in large quantities, to convert as a reactant. Strategies to eliminate carbon deposition, which is the major problem associated with this reaction, are discussed. The oxidative coupling of methane directly produces ethylene in one reactor through a slightly exothermic reaction, potentially minimizing the capital cost of the natural gas conversion process. The focus of discussion in this review will be on the attainable yield of C2 products by rigorous kinetic analyses.

Promoting Effect of Cerium Oxide on the Catalytic Performance of Yttrium Oxide for Oxidative Coupling of Methane

“…The development of highly active OCM catalyst has been continuously performed over the past few decades (Hutchings et al, 1989; Arndt et al, 2011; Takanabe, 2012; Farrell et al, 2016) since the pioneering works of Keller and Bhasin (1982). The OCM reaction proceeds via the formation of methyl radicals formed by the reaction of methane with active oxygen species and subsequent coupling the methyl radicals (Dubois and Cameron, 1990).…”

Oxidative coupling of methane over Mn–Na2WO4/SiO2 catalyst with continuous supply of alkali chloride vapor

“…The direct conversion of methane into valuable chemicals without the need for energy-intensive intermediate syngas production is a difficult but rewarding challenge [1][2][3]. The oxidative coupling of methane (OCM) to give ethylene and ethane is one of an attractive direct route [4], but product yields are below the levels required for industrial applications [5].…”

Revisiting the oxidative coupling of methane to ethylene in the golden period of shale gas: A review

“…Clearly, the projected future global 24 escalations in energy demands hinted that, the major roles that 25 conventional natural gas will play are associated with certain 26 uncertainties [1,2]. Therefore, the exploration and utilization of 27 shale gas could play an important role in addressing some of these 28 uncertainties [3][4][5][6][7][8].…”

“…Our current review will therefore 91 tailor recent studies with the view of identifying the progress 92 made. In 2012, Takanabe [25] have also reviewed good number of 93 literature on the main reaction mechanisms. His findings include 94 substantial argument on the formation of gaseous H , OH and CH 3 95 radicals during some intermediate steps of the reaction.…”

“…These OH radicals were reportedly 104 believed to be generated from an equilibrated interaction of 105 oxygen with water. Takanabe [25], later reported that, further 106 investigations involving improved catalysts design and optimal 107 selection of reaction conditions with the view of enhancing 108 ethylene yields (i.e. the cumulative amount of ethylene generated 109 during the reaction) and promoting how the oil and gas industry 110…”