Catalytic hydrogenation of CO2 into methanol and dimethyl ether over Cu-X/V-Al PILC (XÂ =Â Ce and Nb) catalysts

•The CuNb/V-Al PILC and CuCe/V-Al PILC catalysts showed the highest CO2 conversion.•MeOH, DME, CH4 and CO were the main products formed under all temperatures.•The CuCe/V-Al PILC catalyst was the most promising catalyst for DME synthesis.•MeOH and DME were directly related to the Cu+ and CuO species, acid and basic sites.

The production of methanol (MeOH) and dimethyl ether (DME) through CO2 hydrogenation is an attractive route to recycle CO2 and control its emission to the atmosphere. In the present work, the hydrogenation of CO2 into MeOH and DME over Al-pillared clays impregnated with different metals (Cu-X/V-AI PILC, where X = Ce and Nb) was investigated in the temperature range 200-300 °C. The influence of additives on the physico-chemical properties of the catalysts was evaluated by N2 adsorption, ex situ XRD, TPR analysis, and in situ XANES and XRD. The acid sites were analyzed by FTIR analysis after adsorption of pyridine and NH3-TPD. The basic and metallic sites were analyzed by CO2-TPD and N2O-TPD, respectively. In situ XANES was used to investigate the Cu+ and CuO species. MeOH and DME selectivities were directly related to the presence of acid, basic and metallic sites and with the reaction temperature. The results indicated that the CuCe/V-Al PILC catalyst was the most promising catalyst for DME synthesis from CO2.

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