复合分子筛β/SBA-15的合成及表征

Synthesis and Characterization of Composite Molecular Sieves Beta /SBA-15

以β分子筛为部分硅铝源,正硅酸乙酯为硅源,P123为模板剂,采用后合成法在水热条件下制备复合分子筛β/SBA-15。考察了酸浓度、酸体积、晶化温度和晶化时间等合成条件对合成样品的影响。通过XRD、红外(FTIR)、N2吸附-脱附等表征手段对其结构进行了表征,结果表明,酸浓度为6 mol/L,酸体积40 mL,β加入量50%(占样品质量分数),晶化温度110℃,晶化时间48 h为最佳合成条件,β次级结构单元进入SBA-15孔壁中,孔壁变厚。然后,将Hβ、机械混合分子筛、复合样品的苯酚烷基化催化效果进行对比,表明合成样品优于机械混合型分子筛。

With commercial beta molecular sieve as part of the silicon aluminum source, TEOS as silicon source and P123 as the template agent, composite molecular sieves beta/SBA - 15 were prepared by adopting the after-synthesis under hydrothermal conditions. The effects of synthesis conditions, including acid concentration, acid volume, crystallization temperature and time, on the synthetic samples were investigated, and their structures were characterized by adopting XRD, FTIR and N2 adsorption-desorption methods. The results show that the acid concentration 6 mol/L, 40 mL acid volume ,beta load 50% ,crystallization temperature of 110 ℃ and 48 h crystallization time are the best synthesis conditions. When beta secondary structural units entered the SBA -15 hole in the wall, the hole wall becomes thickening. A comparison of the catalytic effect of phenol alkylating between beta, mechanical mixing and the synthetic samples in this study clearly indicates that the sample is better than the mechanical mixing molecular sieve.