Abstract: A dialkyl carbonate is prepared by reacting urea with an alkyl monohydric alcohol at 70° C. to 150° C. under normal pressure or reduced pressure. The reaction is conducted for 6 h to 30 h under stirring and reflux, with one or more of magnesium, calcium, aluminum, chromium, manganese, iron, cobalt, nickel, copper and zinc as a primary catalyst and one or more compounds including an electron-donating nitrogen, phosphonis, oxygen or sulfur atom as a catalyst promoter. The dialkyl carbonate is prepared under low reaction temperature and normal pressure or reduced pressure, with high selectivity and high yield. With simple operations, high safety and low cost for the process, the method has prominent industrial application prospects.

Abstract: A dialkyl carbonate is prepared by reacting urea with an alkyl monohydric alcohol at 70° C. to 150° C. under normal pressure or reduced pressure. The reaction is conducted for 6 h to 30 h under stirring and reflux, with one or more of magnesium, calcium, aluminum, chromium, manganese, iron, cobalt, nickel, copper and zinc as a primary catalyst and one or more compounds including an electron-donating nitrogen, phosphonis, oxygen or sulfur atom as a catalyst promoter. The dialkyl carbonate is prepared under low reaction temperature and normal pressure or reduced pressure, with high selectivity and high yield. With simple operations, high safety and low cost for the process, the method has prominent industrial application prospects.