Progress on the catalytic hydrogenation of CO2 via reverse water gas shift reaction

The excess emission of CO2 through the combustion of fossil fuels, have triggered a severe crisis to the carbon balance in the earth's ecological system and thus threatened the sustainable development of our economy and society. An attractive way to mitigate the problem is to utilize CO2 and the excess H2 generated from renewable energy sources, to produce CO via the reverse water gas shift reaction (RWGS), which can be used as feedstock in the successive Fischer-Tropsch synthesis, and therefore could replace partially the coal-to-syngas route. Meanwhile, this strategy could provide a reference to the abandoned wind and light energy issues. In this review, the catalytic systems for the study of RWGS reaction in recent years were summarized, including supported metal catalysts, metal oxide catalysts and transition metal carbide catalysts. We also introduced the reaction mechanisms of RWGS reaction over different types of catalysts. The factors affecting the selectivity of CO2 hydrogenation to CO were analyzed, mainly including the particle size of active component, supports, promoters, reaction conditions, as well as the strategy to improve the catalyst stability when exposed to a high temperature environment. Moreover, the advantages and disadvantages of different catalysts in the RWGS reaction were discussed, which can provide a guidance for the development of high-performance RWGS catalysts with increases CO selectivity and life. © 2016, Chemical Industry Press. All right reserved.