甲醇和碳酸丙烯酯合成碳酸二甲酯的研究

采用浸渍法以ZrO2为载体，以碱金属氢氧化物和碳酸盐为前驱体制备了不同的固体碱催化剂，在温和反应条件下考察了催化剂的酯交换扳应性能，并通过BET、XRD和CO2－TPD等方法对催化剂进行了表征，结果表明：Na2CO3负载到不同载体上，其催化性能明显不同，Na2CO3/ZrO2催化剂获得了较高的酯交换活性。载体的比表面和孔结构与催化剂的反应活性无一定的依存关系。而催化剂表面的酸碱性是影响酯交换活性的重要因素。

SYNTHESIS OF DIMETHYL CARBONATE FROM METHANOL AND PROPYLENE CARBONATE

Dimethyl carbonate (DMC) has attracted much attention in terms of a substitute for highly toxic phosgene and dimethyl sulfate in the organic synthesis. Additionally, DMC is considered to be an option for meeting the oxygenate specification of liguid fuel. In this paper, the solid base catalysts are used for DMC synthesis via the ester exchange reaction between propylene carbonate and methanol. Na 2CO 3/ZrO 2 catalysts were prepared by impregnating ZrO 2 support with sodium carbonate aqueous solution followed by drying and calcinating in air. The catalysts characterization by TPD, BET and XRD indicated that the total amount of basic active sites on the catalysts were important for ester exchange reaction of methanol and propylene carbonate. The surface area and pore volume of the supports effected slightly on the catalytic performance. Na 2CO 3/ZrO 2 catalyst showed highest activity (PC conversion 45.43%, DMC yield 40.30%) comparing to Na 2CO 3/MgO due to its stronger basicity as well as more basic sites. The optimum calcined temperature and Na 2CO 3 content are 873?K and 25?w /% respectively.