Abstract
This study critically reviews the mechanism of CO2 hydrogenation over Ni, Ru and Cu, and
the effect of catalyst properties and operating conditions on reaction kinetics. Most studies have
reported the presence of CO and formate species on Ni-, Ru- and Cu-based catalysts, where
subsequent conversion of these species depends on the type of catalyst and the physicochemical
properties of the catalyst support. Methane is the major product that forms during CO2
hydrogenation over Ni and Ru catalysts, while methanol and CO are mainly produced on Cu
catalysts. A different approach for catalyst formulations and/or process development is
required where long chain hydrocarbons are desired.