共沉淀浸渍法制备由合成气直接合成二甲醚的Cu-Mn催化剂

Cu-Mn-Zn/Y catalyst prepared by the co-precipitation impregnation method for the synthesis of DME was investigated. It was found that the molar ratio of Zn to Mn had great effect on the activity and selectivity of the catalyst. The superfluous Mn content restrained the synthesis of DME faintly. The excess content of Zn lowered the conversion of CO greatly. The zeolite Y influenced the activity of dehydrating component and the proportion of Cu-Mn-Zn content in combination of the catalyst. The surplus Y-zeolite reduced the conversion of CO and the selectivity of DME. From this results, when the ratio of n(Zn)/n(Mn) was 1/3～1/2 and the content of Y-zeolites was 33% in the Cu-Mn-Zn/Y catalyst, the CO conversion and the DME selectivity reached 66% and 68%, respectively, at the conditions of 245 ℃. 2.0 MPa, 1500 h-1 and V(H2)/V(CO)=1.5. When the CO conversion and the DME selectivity were taken into all-around account, the best reaction temperature was about 260 ℃.