CO_2 hydrogenation to methanol over CuO-ZnO-ZrO_2 catalysts prepared via a CTAB-assisted co-precipitation method: Effect of catalyst compositions

摘要

In this study, CuO-ZnO-ZrO_2 catalysts were synthesized via a cetyltrimethyl ammonium bromide-assisted coprecipitation method. Effects of ZrO_2 content on the physicochemical properties of the resulting catalyst as well as their catalytic performance for CO: hydrogenation have been investigated. The catalysts were characterized by means of inductively coupled plasma optical emission spectroscopy (ICP-OES), N_2-sorption, N_2O chemical sorption, X-ray diffraction and H_2-temperature program reduction. The characterization data of the obtained catalysts showed that the physicochemical properties of the catalysts can be controlled by varying the chemical composition. The increase of Zr content was found to remarkably improve the dispersion of CuO, which provided the maximum yield of methanol at a low reaction temperature. Among all catalysts, the catalyst prepared with 40 mole% Zr (40C20Z40Z catalyst) exhibited the highest yield of methanol of 84.15 g_(methanol)/kg_(catalyst)·h. at the reaction temperature and pressure of 240 °C and 20 bar, respectively.