SO_4^(2–)/TiO_2-SnO_2固体酸催化剂的制备及其催化合成丙烯酸苄酯

Preparation of SO_4^(2–)/TiO_2-SnO_2 solid acid catalyst and its catalytic activity in synthesis of benzyl acrylate

采用共沉淀法制备了SO_4^(2–)/TiO_2-SnO_2固体酸催化剂,利用SEM-EDS、XRD、FTIR、Py-IR、XPS等技术对其进行了表征,结果表明:Sn掺杂会改变催化剂晶型结构与酸性中心的数量和分布情况。在Sn掺杂量为5%、焙烧温度为500℃条件下,将其用于丙烯酸苄酯合成,显示了良好的催化活性。通过对反应条件进行优化,结果表明:酸醇摩尔比为1.3∶1、催化剂用量3%、反应温度120℃时,反应苯甲醇的转化率为93.1%,产物选择性为98.8%。与SO_4^(2–)/TiO_2相比,其反应活性与稳定性显著提高,抗结焦能力增强。

SO4 2–/TiO2-SnO2 solid acid catalysts prepared by co-precipitation method and then were characterized by SEM-EDS,XRD,FTIR,Pyridine-IR and XPS.The result showed that crystal structure of the catalyst,and the quantity and distribution of the acid centers were changed by doping Sn.The catalyst doped with 5%Sn and calcined at 500℃showed excellent catalytic activity in the synthesis of benzyl acrylate.Under the optimal conditions of 3%catalyst,reaction temperature of 120℃,and ratio of acid and olefin of 1.3∶1,the conversion of phenylcarbinol was 93.1%and the selectivity of the product was 98.8%.Compared with SO4 2–/TiO2,the reactivity,stability and the anticaking ability were significantly improved.