(560az) Hydroxyl-Mediated Ethanol Selectivity of CO2 hydrogenation | AIChE

(560az) Hydroxyl-Mediated Ethanol Selectivity of CO2 hydrogenation


Yang, C. - Presenter, Tianjin University
Gong, J., Tianjin University
Mu, R., School of Chemical Engineering and Technology, Tianjin University
Oxide-supported Rh nanoparticles have been widely used for CO2 hydrogenation, especially for ethanol synthesis. However, this reaction operates under high pressure, up to 8 MPa, and suffers from low CO2conversion and alcohol selectivity. This paper describes the crucial role of hydroxyl groups bound on Rh-based catalysts supported on TiO2 nanorods (NRs). The RhFeLi/TiO2 NR catalyst shows superior reactivity (≈15% conversion) and ethanol selectivity (32%) for CO2 hydrogenation. The promoting effect can be attributed to the synergism of high Rh dispersion and high-density hydroxyl groups on TiO2 NRs. Hydroxyls are proven to stabilize formate species and protonate methanol, which is easily dissociated into *CHx, and then CO obtained from the reverse water–gas shift reaction (RWGS) is inserted into *CHx to form CH3CO*, followed by CH3CO* hydrogenation to ethanol.