苄基磺酸化MCM-41介孔分子筛的合成、表征及性能研究

Synthesis，Characterization and Photocatalytic Properties of

摘要:

MCM-41介孔分子筛分别与苄基氯和氯磺酸接枝反应，得到苄基磺酸介孔分子筛（SBM）。通过X射线多晶衍射（XRD）、氮气吸附脱附、红外光谱（IR）、有机元素分析、扫描电镜（SEM）等方法对所得样品进行了表征。研究结果表明，MCM-41表面硅羟基与苄基氯反应，C接枝量（w%）达到5.84%。进一步磺化，S接枝率（w%）可达7.46%。XRD等分析结果表明，经过两步接枝反应，SBM仍然具有介孔结构特征，比表面积和孔容分别为366.9 m2•g-1、0.349 cm3•g-1。以SBM为催化剂，催化合成柠檬酸三丁酯。结果表明，当n(酸)：n（醇）=1.0∶9.0，w（cat）=3%，反应温度为110 ℃，回流时间7 h，酯化率可达93.22%。且催化剂可重复使用，重复五次，酯化率仍然为76.33%。

Abstract:

Benzalhydantoin sulfonic mesoporous (SBM) was gotted by MCM-41 graftting with benzyl chloride and chlorosulfonic respectively. The composition ,structure and surface physical and chemical properties of the samples were characterized by surface of elemental analysis (EDS), fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and so on. The results of EDS and organic elemental analysis shows that the grafting yield was 5.84% of C（w%） for BM (sample, MCM-41 Si-OH graftting with benzyl chloride) . Further sulfonation, S grafting ratio (w%) was up to 7.46% for SBM. The results show that, after a two-step grafting reaction, SBM still has a mesoporous structure. The BET surface area is 366.9 m2•g-1and the pore volume is 0.349 cm3•g-1． The process for synthesis of tri-n-butyl citrate using SBM as catalyst was studied. The results show that when n (acid): n (alcohol) = 1.0:9.0, w (cat) = 3%, the reaction temperature is 110 ℃, reflux time 7 h, yield was 93.22%. And the catalyst can be reused, repeated five times, the esterification rate remains at 76.33 %.