W-MCM-48中孔分子筛的微波合成与表征

Synthesis and Characterization of Mesoporous Molecular Sieve W-MCM-48 by Microwave Radiation

在微波辐射下快速合成出W MCM 48分子筛 ,通过XRD ,FT IR和N2 吸附等手段对样品进行了表征 ,并考察了合成条件对W MCM 48相对结晶度的影响 .结果表明 :在微波辐射下快速合成出的W MCM 48分子筛结晶及热稳定性良好 ,且孔道规整 ;W离子进入了分子筛的骨架 ;以十六烷基三甲基溴化铵为模板剂 ,最佳合成条件为n(Na2 O) /n(SiO2 ) =0 2 5,p =0 48MPa ,t=2h .苯乙烯催化氧化实验表明 ,W MCM 48具有一定的催化性能 .

Tungsten containing mesoporous molecular sieve W MCM 48 was rapidly synthesized by microwave radiation. The samples were characterized by XRD, FT IR and N 2 adsorption techniques. Effects of synthetic conditions on relative crystallinity of W MCM 48 were studied. The results show that the W MCM 48 has uniform mesopore channels, high thermostability and good crystallinity. FT IR spectra of W MCM 48 samples affirm that the tungsten cations are incorporated into the framework of W MCM 48. W MCM 48 can be best prepared under the following conditions: using CTMABr as the template, n (Na 2O)/ n (SiO 2) =0 25, p =0 48 MPa and t R=2 h. But the effect of ageing time t A is negligible. In the catalytic oxidation of PhCH∶CH 2 with H 2O 2, W MCM 48 shows good performance.