核壳结构TiO_2@SiO_2催化碳酸二甲酯与苯酚酯交换合成碳酸二苯酯  

Core-shell TiO_2@SiO_2 catalyst for transesterification of dimethyl carbonate and phenol to diphenyl carbonate

作　　者：唐荣芝[1,2] 陈彤[1] 陈勇[3] 张元卓[1,2] 王公应[1] 

机构地区：[1]中国科学院成都有机化学研究所,四川成都610041 [2]中国科学院大学,北京100049 [3]后勤工程学院国防建筑规划与环境工程系,重庆401311

出　　处：《催化学报》2014年第4期457-461,共5页

基　　金：国家高技术研究发展计划(863计划;SS2013AA031703);四川省科技支撑计划(2013GZX0135);四川省青年科技创新研究团队项目(2013TD0010)~~

摘　　要：以反相微乳液法和沉淀法相结合制备了核壳结构TiO2@SiO2,首次用于碳酸二甲酯与苯酚酯交换合成碳酸二苯酯反应,显示较好的催化活性.采用200°C焙烧的TiO2@SiO2,用量0.20 g,反应9 h,苯酚转化率达41.8%,酯交换选择性为100%.透射电镜显示TiO2@SiO2核厚壳薄,TiO2核直径220–300 nm,SiO2壳厚度40–60 nm,具有介孔结构.TiO2@SiO2对碳酸二甲酯与苯酚酯交换反应有好的重复使用性,使用4次苯酚转化率仍保持在40%以上.TiO2与SiO2发生相互作用,Ti进入骨架形成Ti–O–Si键,骨架Ti的形成提高了TiO2@SiO2的催化性能.Core-shell TiO2@SiO2 was prepared using a combination of reverse microemulsion and precipita-tion methods and used as a heterogeneous catalyst for the transesterification of dimethyl carbonate and phenol. TiO2@SiO2 calcined at 200 ℃ gave the best catalytic performance. When the amount of catalyst was 0.20 g, the phenol conversion and transesterification selectivity were 41.8% and 100%, respectively. Transmission electron microscopy was used to characterize the core-shell TiO2@SiO2 structure, and the results showed that TiO2@SiO2 is bilayer with a TiO2 core of diameter 220-300 nm and SiO2 shell of thickness 40-60 nm. The TiO2@SiO2 was reusable, and phenol conversion re-mained above 40% when the TiO2@SiO2 was used four times. The catalytic performance of TiO2@SiO2 in the transesterification of dimethyl carbonate and phenol was promoted by the for-mation of Ti-O-Si bonds.

关 键 词：核壳结构 TiO2SiO2 碳酸二苯酯 碳酸二甲酯 酯交换 

分 类 号：TQ245.2[化学工程—有机化工]