Ti-HMS分子筛的合成、表征及催化性能研究

以十二胺为模板剂，正硅酸乙酯为硅源，钛酸四丁酯为钛源，于室温下合成了含Ti中孔分子筛Ti-HMS。通过改变Ti的用量得到了一系列不同硅／钛摩尔比（n（SiO2）／n（TiO2））的样品，采用XRD、TEM、XRF、UV-Vis等手段对这些样品进行表征；利用二苯并噻吩（DBT）和4，6-二甲基二苯并噻吩（4，6-DMDBT）氧化反应、丙烯环氧化反应、1-丁烯环氧化反应、环己酮氨氧化反应评价了所得样品的催化性能。结果表明，Ti-HMS分子筛多为20～70nm的球状颗粒，且具有2～3nm的蠕虫状（Worm-like）孔道；随着合成原料中Ti量的增加，进入Ti-HMS的骨架Ti量增多，但非骨架Ti也增多；随着骨架Ti含量的增加，样品的催化性能提高；Ti—HMS在大分子反应中的催化活性较高，在小分子反应中的催化活性不及TS-1。

SYNTHESIS, CHARACTERIZATION AND CATALYTIC PERFORMANCE OF Ti-HMS MOLECULAR SIEVE

Ti-containing mesoporous molecular sieve Ti-HMS was synthesized at ambient temperature with dodecylamine as template,tetraethylorthosilicalite as Si source and tetrabutylorthotitanate as Ti source.The samples with different n(SiO_2)/n(TiO_2) can be obtained through adding different amount of Ti source,which were characterized by XRD,TEM,XRF and UV-Vis.The catalytic performance of Ti-HMS was evaluated in the oxidation of DBT and 4,6-DMDBT,the propylene epoxidation,the 1-butylene epoxidation and the ammoxidation of cyclohexanone.The results showed that the particles of Ti-HMS were spherical with the size of 20-70 nm and possessed worm-like channel with the size of 2-3 nm.With the increase of Ti content in raw materials,more Ti atoms entered the framework,and the Ti content of extra-framework also increased.Ti-HMS showed better catalytic performance in the oxidation of large molecules,but worse performance in small molecular reactions than TS-1.