Enhanced activity of CuFe/SiO2 catalyst for CO hydrogenation to higher alcohols by pretreating the support with ammonia

The effect of support pretreatment with ammonia on the performance of CuFe/SiO2 catalyst for higher alcohols synthesis from syngas was studied by CO hydrogenation, X-ray diffraction, N2 adsorption–desorption, temperature-programmed reduction of H2, Fourier transform infrared spectroscopy, N2O chemisorption and temperature-programmed desorption of adsorbed CO. The results indicated that the pretreatment of SiO2 with ammonia resulted in the formation of more active sites of Cu and higher dispersion of Fe species on the catalyst surface and enhanced the synergistic effect between the copper and iron species. As a result, the CO conversion and the space time yield of alcohols of the CuFe/SiO2 catalyst increased from 14.8% and 89.0 g kg−1 h−1 to 17.4% and 107.0 g kg−1 h−1, respectively.