Bi-MSU-4分子筛合成、结构及催化性能的研究  

Study on the synthesis,structure and catalytic performance of Bi-MSU-4 silicas molecular sieves

作　　者：王玉[1] 鄢红艳[2] 陈晓晖[1] 魏可镁[1] 

机构地区：[1]福州大学化肥催化剂国家工程研究中心,福建福州350002 [2]大冶有色金属公司冶炼厂,湖北黄石435005

出　　处：《功能材料》2008年第4期636-640,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(20306004,20671020)

摘　　要：以聚氧乙烯失水山梨醇酸酯(Tween-x,x=20、40、60、80)为模板剂,正硅酸乙酯为硅源,在室温条件下首次合成了含有骨架金属元素铋的介孔分子筛T-20、40、60、80Bi-MSU-4。采用X射线衍射、傅里叶变换红外光谱、紫外-可见吸收光谱、低温N2吸附/脱附,扫描电镜等手段对样品进行表征,分别考察了模板剂种类、矿化剂、硅铋摩尔比等因素对分子筛结构、骨架形成及催化活性的影响。结果表明,Bi-MSU-4系列具有介孔分子筛典型形貌特征,且金属铋较好地分散于分子筛骨架中。样品的孔径与孔容随模板剂憎水链长度增加而增大,催化活性也相应提高;NaF的矿化作用可促进骨架的成型与脱落;随硅铋摩尔比增加,催化活性先增后减。在苯乙烯氧化反应中,T-xBi-MSU-4有优越的催化性能,其中T60Bi-MSU-4的苯乙烯转化率55.0%,苯甲醛产率41.5%。A kind of mesoporous silica molecular sieves Bi-MSU-4 were synthesized successfully using nonionic ethoxylated sorbitan esters（Tween-x, x=20, - 40, - 60, or - 80） as structure directors respectively and TEOS as silicate source at room temperature. Structures of the synthesized molecular sieves were characterized by X- ray diffraction （XRD）, FT-IR, UV-vis, N2 absorption/desorption and SEM methods. The influence of factors such as templates,mineralizer and Si/Bi molar ratios on Bi-MSU-4 mesoporous structure and styrene catalytic oxidation were examined. The results indicated that Bi-MSU-4 exhibited mesoporous structures and bismuth entered the framework already. The pore size and pore volume of samples increased with the augment of the hydrophobic chain length of templates, which led to the rise of catalytic performance. In addition mineralizing structured framework and expelled it from hydrophilic PEO shell. With the increasing of Si/Bi molar ratio catalytic performance increased first and then decreased. T-xBi-MSU-4 were superior in styrene oxidation reaction and the conversion of styrene was 55.0% and the yield of benzaldehyde was 41.5% especially for T-40Bi-MSU-4.

关 键 词：Bi—MSU-4 物相结构 矿化作用 苯乙烯氧化反应 

分 类 号：O643[理学—物理化学]