Research Progress of Catalysis for Low-Carbon Olefins Synthesis Through Hydrogenation of CO2

Fossil fuel consumption, global warming, climate change, and price fluctuation of fuels push scientists to search for alternative ways to produce fuel. From the viewpoint of CO2 capture and utilization, using CO2 as raw material to produce value-added products is attractive because it can not only alleviate global warming but also offers a solution to replace dwindling fossil fuels. Especially the technique of CO2 hydrogenation to low-carbon olefins including ethylene, propylene and butylene is highly attractive. However, due to the extreme inertness of CO2 and a high C-C coupling barrier, the conversion of CO2 and selectivity of C2-4 are not high. In addition, methane, as one main product in CO2 hydrogenation, inhibits the production of other long-chain hydrocarbons. So it is decisive to design effective catalyst system to increase C2-4 selectivity while decrease CH4 selectivity. This review focuses on two routes for low-carbon olefins synthesis from CO2 hydrogenation. The first route is direct synthesis of low-carbon olefins through CO2 hydrogenation process. The catalyst supports, promoters and bimetallic active components are inextricably related with hydrogenation of CO2 to lower olefins, which was reviewed in detail. The other route is indirect route for low-carbon olefins synthesis through hydrogenation of CO2 to methanol and subsequently methanol to lower olefins, which is briefly discussed.