Hydrogenation of carbon dioxide and carbon monoxide over supported rhodium catalysts under 10 bar pressure

The hydrogenation of carbon dioxide and carbon monoxide was carried out in a 10-atm flow reactor over supported rhodium catalysts. Rh/ZrO2 and Rh/Nb2O5 showed the highest activity for carbon dioxide and hydrogenation, the main product being methane. Methanol was formed selectively from carbon dioxide hydrogen over a Rh/TiO2 catalyst. The products of carbon monoxide hydrogenation over supported Rh catalysts contained higher hydrocarbons and ethanol. The rate of C-C bond formation was higher in carbon monoxide hydrogenation than in carbon dioxide hydrogenation. The effect of the support on hydrogenation of carbon dioxide and carbon monoxide is discussed.