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Hydroxyl-mediated ethanol selectivity of CO₂ hydrogenation.

ABSTRACT: 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 CO₂ conversion 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 *CH _x , and then CO obtained from the reverse water-gas shift reaction (RWGS) is inserted into *CH _x to form CH₃CO*, followed by CH₃CO* hydrogenation to ethanol.

SUBMITTER: Yang C

PROVIDER: S-EPMC6429605 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Hydroxyl-mediated ethanol selectivity of CO2 hydrogenation.

Yang Chengsheng C Mu Rentao R Wang Guishuo G Song Jimin J Tian Hao H Zhao Zhi-Jian ZJ Gong Jinlong J

Chemical science 20190211 11

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 CO2 conversion 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 (3 ...[more]

PMID: 30996897

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