组装在MCM-41和HMS上的Ti活性中心的催化作用  

Catalytic Properties of Titanium Centers Assembled on MCM-41 and HMS

作　　者：尹笃林[1] 伏再辉[1] 赵伟[1] 王辉宪[1] 张鲁西[1] 

机构地区：[1]湖南师范大学精细催化合成研究所,中国长沙410081

出　　处：《湖南师范大学自然科学学报》2002年第2期45-48,57,共5页Journal of Natural Science of Hunan Normal University

基　　金：国家自然科学基金资助项目 (2 9972 0 11和 2 97730 13)

摘　　要：采用模板组装途径合成MCM 4 1和HMS两类中孔材料 ,探讨了在含模板剂和烧去模板剂的这两类载体上键合两类酒石酸钛络合物的组装方法 .XRD和FT IR结果表明 :在焙烧过程中 ,MCM 4 1长程有序的中孔结构会发生退化而转化成与HMS相似的结构 ,并导致 12 19和 5 80cm- 1 红外带的消失 ,而诱发载体产生强的Si—OH畸变 .中孔HMS与钛化合物的键合作用会诱发载体产生弱的Si—OH畸变振动 .在催化苯乙烯环氧化反应中 ,模板剂和酒石酸二乙酯 (DET)Mesoporous silicas MCM-41 and HMS were synthesized by the cooperative assembly of silica and surfactants. Two methods are raised to assemble titanium tartrate complexes over the untreated and calcined mesoporous carriers. The results of XRD and FT-IR indicate that MCM-41's mesostructure with long-range order will deteriorate, and be transformed into the mesostructure similar to HMS. This deterioration of the mesostructure arises the disappearance of 1 219 and 580 cm-1, and then also causes a stronger aberrance of MCM-41's Si-OH groups. The binding of HMS with Ti complexes will induce the Si-OH groups of HMS to produce a weaker aberrance. In the epoxidation of styrene, the assembled Ti catalysts with the calcined mesoporous carriers exhibit the highest oxidative activity, and the assembled Ti catalysts with untreated mesoporous carriers possess the best epoxide selectivity. The modification of the templating agents and diethyl tartrate (DET) ligand on the Ti active centers will cause the decreases in the actalytic activity and the increases in the selectivity.

关 键 词：MCM-41 HMS 中孔硅载体 钛络合物 催化作用 苯乙烯 环氧化反应 模板组装 钛活性中心 

分 类 号：O643.361[理学—物理化学]