Influence of manganese promoter on co-precipitated Fe–Cu based catalysts for higher alcohols synthesis

Effect of manganese promoter on the microstructures of co-precipitated Fe–Cu catalysts was investigated by N2 physisorption, X-ray diffraction (XRD), and temperature-programmed reduction/desorption of hydrogen (H2-TPR/TPD). Higher alcohols synthesis (HAS) was performed in a fixed bed reactor. The characterization results indicated that incorporation of manganese into the Fe–Cu based catalysts facilitated the formation of Fe–Mn–O solid solution and promoted the dispersion of both the iron and copper species. In the HAS reaction, the catalytic activity of CO hydrogenation, selectivity of C 2 + OH and hydrocarbons increased gradually with increasing Mn concentration, which may be attributed to the well dispersion of both the iron and copper surface active sites in higher manganese content. The optimum conditions for producing higher alcohols from syngas were determined as 270 °C and 6.0 MPa.