Catalytic valorization of CO₂ by hydrogenation: current status and future trends

Abstract

Terrestrial environmental and biological systems are being threatened by the tremendous amount of human carbon dioxide emissions. Therefore, is crucial to develop a sustainable energy system based on CO2 as chemical feedstock. In this review an introduction to the CO2 activation and transformation has been made, together with a more comprehensive study of the catalytical reduction of CO2 to methane, methanol and formic acid, which are currently contemplated as chemical feedstocks and/or promising energy carriers and alternative fuels.

Advances in studies of the structural effects of supported Ni catalysts for CO2hydrogenation: from nanoparticle to single atom catalyst

“…Methane is normally the main product below 600 °C. 28 A further increase in the reaction temperature causes CO formation. 11,28,36,37 100% selectivity to CO can be observed at 750 °C.…”

“…28 A further increase in the reaction temperature causes CO formation. 11,28,36,37 100% selectivity to CO can be observed at 750 °C. 28 This suggests that the exothermic CO 2 hydrogenation to methane dominates at temperatures below 600 °C, whereas the RWGS reaction is the predominant one at temperatures above 600 °C.…”

“…28 This suggests that the exothermic CO 2 hydrogenation to methane dominates at temperatures below 600 °C, whereas the RWGS reaction is the predominant one at temperatures above 600 °C. 28…”

“…A change in the electronic structure can cause a big change in the selectivity. 26–35 One can shift the selectivity of CO 2 hydrogenation from selective production of methane to methanol or CO or even formic acid by the change of the catalyst structure. The electronic structure of a supported Ni catalyst can be tuned by the physical structure and components, including the supporting material, of the catalyst.…”

CO2 reduction into formic acid under hydrothermal conditions: A mini review

“…On the other hand, CO 2 can also be used as a non‐toxic, low cost and easily available C 1 source to synthesize highly value‐added fine chemicals 4‐6 . Formic acid is widely used in rubber, medicine, pesticides, dyes, fuel cells, agriculture and environmental protection and can be generated from CO 2 hydrogenation (CO 2 + H 2 = HCOOH) with the atom's economic efficiency of 100% 7‐9 . More importantly, the conversion of CO 2 to formic acid that turns waste into valuable substances could achieve the Sustainable Development Goals related to the energy cycle.…”