A new MoO3/SO4 2--TiO2 catalyst was prepared by a conventional impregnation of SO4 2-/TiO2 as carrier with an aqueous solution of ammonium molybdate and used for the synthesis of transesterification of dimethyl carbonate(DMC)with phenol.A series of MoO3/SO4 2--TiO2 catalysts with different MoO3 loadings were investigated and characterized using X-ray diffraction(XRD),Fourier transform infrared spectrometer(FTIR),NH3-temperature programmed desorption(NH3-TPD)and X-ray photoelectron spectroscopy(XPS).The results show that MoO3 loading is related to the activity of transesterification reaction.With the increase of MoO3 loading,the activity of transesterification reaction increases.The sulfur species in the catalyst have an influence on the molybdenum species,and lead to an increase in the electropositive of molybdenum,which promotes the catalytic activity of MoO3/SO4 2--TiO2.Among the series of catalysts prepared,MoO3/SO4 2--TiO2 with 10% MoO3 and 823 K calcinated is found to be the most active catalyst for transesterification reaction.Under the reaction conditions of 453 K and 12 h,the conversion of DMC is 30.5 %,and the yields of MPC and DPC reach 21.2 % and 8.7 %,respectively.
