Study on reaction performance of copper salt in oxidative carbonylation of ethanol

The CuBr₂/DMA (N, N-dimethylacetamide) homogeneous catalyst system was selected to be used for the reaction process of liquid-phase oxidative carbonylation of ethanol. The influences of the catalyst group distribution ratio on catalytic activity, the reaction time on oxidative carbonylation and the recycle performance of CuBr₂/DMA catalyst system were investigated. The results show that the catalyst system exhibits good catalytic activity in oxidative carbonylation. When the concentration of CuBr₂ in DMA solvent is 0.3 g · mL^-1 and reaction time is 2.5 h, the ethanol conversion is as high as 36.2%. XRD characterization shows that the active center of copper catalyst is Cu (II), which is tranfered to Cu (I) at the beginning of reaction. In catalyst cycle experiment, the active center of copper catalyst is Cu (I), and the stability of CuBr in DMA solvent is comparable to CuBr₂. The analyses of liquid products by using gas chromatography and gas chromatography - mass spctroscopy show that the products are diethyl carbonic, ethyl formate, ethyl acetate and ethyl propionate. On the basis of the above results, the formation of product and possible catalytic mechanism was explored.