Dimethyl carbonate synthesis by liquid-phase oxidative carbonylation with CuBr_nL_m complex catalyst

A new type of CuBrnLm complex catalyst for dimethyl carbonate(DMC) synthesis by oxidative carbonylation of methanol in liquid-phase was reported.The reaction properties and stability of the catalyst was studied.CuBrnLm complex catalysts were characterized with FTIR,XPS and EPR.The results showed that the introduction of complex L could promote the substantial formation of Cu(I) species for DMC synthesis.With the method of orthogonal design,the process conditions(temperature,concentration of catalyst,pressure and reaction time) were optimized.The results indicated that under the optimum conditions(temperature 100—110 ℃,pressure3.0—3.5 MPa,4—6 h,the mass concentration of catalyst(by volume of methanol) 0.15—0.20 g/mL),the conversion of methanol could reach 23% and the selectivity of DMC could exceed 95%.