Comparative Study on Ethanol-Based Oxygenate Synthesis via Syngas over Monometallic Rh Catalysts Supported on Different Zr-MOFs

Abstract

Three types of Zr-based metal–organic frameworks (Zr-MOFs) were employed as supports to prepare monometallic Rh catalysts by the impregnation method. The effects of the structural properties of Zr-MOFs on their supported monometallic Rh catalysts for syngas conversion were investigated. The results showed that, compared to catalysts with Rh@MOF-808 and Rh@UiO-66, Rh@UiO-67 had higher CO conversion and C2+ oxygenate selectivity. The state of the Rh site is affected by the different structure of the Zr-MOFs, which is responsible for the difference in catalytic performance. The relatively higher Rh dispersion on the UiO-67 support boosted its CO adsorption ability, and Rh@UiO-67 having the best C2+ oxygenate selectivity was mainly attributed to it having the highest Rh+/Rh0 ratio.