CO2 hydrogenation to dimethyl ether over CuO-ZnO-Al2O3/HZSM-5 prepared by combustion route

CuO-ZnO-Al2O3/HZSM-5 catalysts were prepared and characterized by XRD, BET, N2O titration, H-2-TPR, FESEM and NH3-TPD techniques. CuO-ZnO-Al2O3 catalysts were obtained by a simple and fast urea-nitrate combustion method and then mixed physically with HZSM-5 to perform one step synthesis of dimethyl ether (DME) from carbon dioxide (CO2) hydrogenation. The results showed that the grain size and copper surface areas of the catalysts were highly affected by the amount of urea in the preparation, and their catalytic performances were consequently influenced. A CO2 conversion of 30.6% and DME yield of 15% over the optimal catalyst were obtained by controlling the molar ratio of urea to metal nitrate. The work will benefit the rational design of new catalysts suitable for CO2 utilization.