Energy Sources Part A-recovery Utilization and Environmental Effects, Vol.39, No.15, 1625-1631, 2017
CuZnAl catalysts prepared by precipitation-hydrothermal method for higher alcohols synthesis from syngas
CuZnAl catalysts with different Cu/Zn/Al molar ratio prepared by precipitation- hydrothermal method were evaluated for synthesis of higher alcohols from syngas. All the catalysts were characterized by X-ray diffraction (XRD), H-2 temperature-programmed reduction (H-2-TPR), temperature programmed desorption of ammonia (NH3-TPD-MS) and carbon dioxide (CO2-TPD-MS), and N-2 adsorption. These results show that CuZnAl catalysts with hydrotalcite-like structure exhibited optimum performance in terms of both activity and selectivity to higher alcohols. The catalyst with highly dispersed CuO and suitable interaction between Cu with Zn and Al was favorable for synthesis of higher alcohols. Moreover, the synergistic effect between weak acid sites and medium basic sites promoted the chain propagation and oxygenation. When the molar ratio of Cu/Zn/Al was 0.4: 0.6: 1, the CO conversion could reach 12.5% and the C2+OH selectivity was 13.8%.
Keywords:CuZnAl catalysts;higher alcohols;hydrotalcite-like structure;precipitation-hydrothermal method;syngas