采用双功能硅烷化试剂γ-氨丙基甲基二乙氧基硅烷(AMS),对(MCM-41)全硅介孔分子筛一步进行氨基官能团化和甲基疏水性修饰,然后将双水杨醛缩乙二胺合钴(Cosalen)通过氨基的轴向配位固载在修饰后的载体MCM-41上。X射线衍射和N2物理吸附/脱附的结果表明:经过AMS双功能硅烷化修饰以及固载Cosalen后载体的孔道结构保持良好。考察了硅烷试剂用量对硅烷化效率的影响,结果表明:当AMS的加入量为4.00mmol/g时,甲基修饰量达到1.95mmol/g;水和环己烷的静态吸附结果表明硅烷化修饰后,催化剂载体的疏水性明显增强。制得的催化剂应用于环己烷的分子氧氧化反应,130℃反应2h,环己烷转化率达到7.2%,环己醇和环己酮总选择性达到70.5%,较未经AMS修饰的催化剂Cosalen/MCM-41获得的醇酮总选择性提高了13%。
Silica mesoporous molecular sieve (MCM-411 was bifunctional silylating reagent after Cosalen was immobilized modified with "t-aminopropyl methyl diethoxysilane (AMS) as a on the MCM-41 carrier by axial coordination with amino-group. According to the analysis by nitrogen adsorption-desorption test and X-ray diffraction, the pore structure of Cosalen/AMS- MCM-41 samples after silylation modification and immobilization is intact. The influence of silane reagent amount on the si- lanization efficieney was investigated. When the amount of the AIMS added to MCM-41 carrier is 4. 00 mmol/g, the amount of modified methyl group is 1.95 mmol/g carrier. The results of static adsorption of water and cyclohexane show that the hydro- phobic performance of carrier is improved after bifunctional silylation. The cyclohexane aerobic oxidation reaction is performed at 130 ℃ for 2 h. The conversion of cyclohexane of Cosalen/AMS-MCM-41 is 7.2% and the total selectivity of cyclohexanol/ cyclohexanone is 70.5% , which is 13% greater than that of unmodified catalyst Cosalen/MCM-41.