TS分子筛催化剂上烯丙基氯的环氧化性能

STUDY OF EPOXIDATION OF ALLYL CHLORIDE OVER TS ZEOLITE CATALYSTS

在ＴＳ－１分子筛催化剂上，研究了以Ｈ２Ｏ２为氧源的烯丙基氯液回多相环氧化反应．结果表明，ＴＳ－１－３２分子筛是该反应的有效催化剂，Ｈ２Ｏ２转化率达８０％，目的产物环氧氯丙烷选择性达９０％．用程序升温脱附（ＴＰＤ）和程序升温表面反应（ＴＰＳＲ）研究了Ｈ２Ｏ２和烯丙基氯在催化剂表面的吸附状态．结果表明，ＴＳ－１－３２分子筛对Ｈ２Ｏ２和烯丙基氯有较大的吸附容量和吸附强度，使它们在反应温度下有较大的表面浓度，并使二者充分接触，从而有较高的反应活性；Ｈ２Ｏ２和烯丙基氯的吸附次序对ＴＰＳＲ结果有显著影响；反应温度是ＴＳ－１分子筛上Ｈ２Ｏ２和烯丙基氯吸附的重要参数．

poxidation of allyl chloride over TS zeolite catalysts was reported,and the adspecies of H2O2 and allyl chloride on the catalyst surface werestudied by TPD and TPSR. It was shown that TS-1-32 is an effectivecatalyst for epoxidation of allyl chloride, and that H2O2 conversion of￣80% and the selectivity for desired product, epichlorohydrin, of 90%can be obtained, which is better than that in the case of homogeneouscatalysis. TPD results of H2O2 and allyl chloride over TS zeolite revealed that TS-1-32 zeolite is able to adsorb both H2O2 and allyl chlorideand maintains higher concentrations of them on its surface at the reaction t,emperature, so it exhibits higher catalytic activity for the titled reaction. The TPSR results gave an evidence that the adsorption sequenceof H2O2 and allyl chloride has great influence on the reaction, owing tothe difference between the adsorption strength of H2O2 and allyl chloride. It is clear that the reaction temperature is a crucial parameter forthe reaction, since the adsorption of H2O2 and allyl chloride is obviouslyaffected by the temperature.