Facile Synthesis of Cu/Al2O3 with High Copper Dispersion for Direct Synthesis of Dimethyl Ether from Syngas

The Cu/Al2O3 catalysts were prepared by the solution combustion synthesis method using aluminum nitrate and copper nitrate as oxidants and citric acid as fuel. The Cu/Al2O3 catalysts were characterized by XRD, N-2 adsorption-desorption, SEM-EDS, and H-2-TPR techniques. The test results indicated that this catalyst contained mesoporostity and highly dispersed copper. The Cu/Al2O3 catalysts were utilized as bifunctional catalysts in the syngas-to-dimethyl ether (STD) process. The CO conversion and DME selectivity were 70.9% and 58.8%, respectively. Moreover, the CO conversion kept increasing from 260 degrees C to 320 degrees C thanks to the high copper dispersion, which could reduce copper sintering at high reaction temperatures.