A review on CO2 hydrogenation to ethanol: Reaction mechanism and experimental studies

An increased amount of greenhouse gas emissions, mainly carbon dioxide gas, plays an important role in global warming, drastically affecting the natural pattern. Much research has been performed worldwide regarding how to tackle this situation. One of the solutions is to hydrogenate the CO2 into valuable fuel, which will also suit the available vehicle engines. Ethanol, an essential renewable fuel, can be blended with conventional gasoline and thus increases the octane rating. Hydrogenation of CO2 to ethanol is crucial in lowering the CO2 released by stationary routes such as coal power plants, oil refineries, steel plants, etc. This review focuses on the study of reaction mechanisms and experimental investigation analyzed by researchers in the hydrogenation of CO2 to ethanol using batch and continuous flow reactors at varying reaction conditions. The catalytic stability and recyclability studies also have been discussed.