Textual properties of Cu–Mn mixed oxides and application for methyl formate synthesis from syngas

Abstract

Abstract Cu–Mn mixed oxides with different calcination temperatures were prepared using ammonia complexing method and evaluated for methyl formate (MF) synthesis from syngas with CaO–ZrO2 as co-catalyst. The influence of calcination temperature on the structure and properties of Cu–Mn mixed oxides was investigated by appropriate characterizations. Cu1.5Mn1.5O4 formed during the calcination of Cu–Mn catalyst at 450 °C and played a significant role in the MF synthesis. However, it partially decomposed into CuO and MnO2 when the calcination temperature exceeded 550 °C. Results showed that the optimum MF selectivity was obtained on Cu–Mn catalyst calcined at 450 °C, and the highest CO conversion was obtained on the Cu–Mn sample with calcination temperature of 550 °C. The reaction mechanism of MF synthesis from syngas over Cu–Mn mixed oxides and CaO–ZrO2 co-catalyst was thoroughly studied via typical model reactions, and the nucleophilic addition–elimination reaction mechanism was proposed.