Reaction mechanisms of carbon dioxide methanation

Constant increase of carbon dioxide emissions from anthropogenic activities leads to the search of options for its recycling and utilization. Although recycled CO2 utilization as a raw material for the production of chemicals and propellants can be challenging, it is the most sustainable way to mitigate its emissions. Among the most promising applications of CO2 is its catalytic fixation with hydrogen via the methanation reaction to methane. CO2 methanation, depending on the used catalyst and overall reaction conditions, can proceed through different mechanism or pathways. A literature review on the methanation reaction mechanism shows that CO2 can be converted to methane either by direct methanation or through the formation of a CO intermediate. This article analyses the proposed reaction mechanisms of CO2 methanation.