Direct synthesis of dimethyl carbonate form methanol and carbon dioxide using H3PW12O40/Ce0.1Ti0.9O2 with ionic liquid catalysts

H3PW12O40/Ce0.1Ti0.9O2 and imidazolium salt ionic liquid catalysts were prepared and applied to the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The effect of reaction temperature, reaction time, pressure of carbon dioxide and amount of H3PW12O40/Ce0.1Ti0.9O2 in the presence of ionic liquid are discussed. The results showed that H3PW12O40/Ce0.1Ti0.9O2 is an effective catalyst. The high selectivity and higher yield of DMC were achieved. The combination of imidazolium salt and H3PW12O40/Ce0.1Ti0.9O2 could evidently improve the yield of the product. The maximum DMC yield reached up to 12.98% in the presence of EMImCl at 140 degrees C and 2.4 MPa.