Carbon Dioxide Reduction with Hydrogen on Fe, Co Supported Alumina and Carbon Catalysts under Supercritical Conditions

Viktor I Bogdan; Aleksey E Koklin; Alexander L Kustov; Yana A Pokusaeva; Tatiana V Bogdan; Leonid M Kustov

doi:10.3390/molecules26102883

Carbon Dioxide Reduction with Hydrogen on Fe, Co Supported Alumina and Carbon Catalysts under Supercritical Conditions

Molecules. 2021 May 13;26(10):2883. doi: 10.3390/molecules26102883.

Authors

Viktor I Bogdan^{1

2}, Aleksey E Koklin¹, Alexander L Kustov^{1

2}, Yana A Pokusaeva¹, Tatiana V Bogdan^{1

2}, Leonid M Kustov^{1

2}

Affiliations

¹ N.D. Zelinsky Institute of Organic Chemistry, Leninsky Prospect, 47, 119991 Moscow, Russia.
² Chemistry Department, Lomonosov Moscow State University, Leninskie Gory, 1, Bldg. 3, 119992 Moscow, Russia.

Abstract

Reduction of CO₂ with hydrogen into CO was studied for the first time on alumina-supported Co and Fe catalysts under supercritical conditions with the goal to produce either CO or CH₄ as the target products. The extremely high selectivity towards methanation close to 100% was found for the Co/Al₂O₃ catalyst, whereas the Fe/Al₂O₃ system demonstrates a predominance of hydrogenation to CO with noticeable formation of ethane (up to 15%). The space-time yield can be increased by an order of magnitude by using the supercritical conditions as compared to the gas-phase reactions. Differences in the crystallographic phase features of Fe-containing catalysts cause the reverse water gas shift reaction to form carbon monoxide, whereas the reduced iron phases initiate the Fischer-Tropsch reaction to produce a mixture of hydrocarbons. Direct methanation occurs selectively on Co catalysts. No methanol formation was observed on the studied Fe- and Co-containing catalysts.

Keywords: carbon dioxide; carbon monoxide; cobalt nanoparticles; iron nanoparticles; methane; supercritical CO2.