硅钨酸负载介孔分子筛SBA-15的制备及催化性能研究

Preparation and Catalytic Performance of Mesoporous Molecular Sieve SBA-15 Modified with Silicotungstic Acid

[目的]探讨负载型介孔分子筛SiW12/SBA-15的制备及催化性能。[方法]采用水热合成法,以P123为模板剂制备介孔材料SBA-15,由硅钨酸浸渍进一步合成介孔催化剂SiW12/SBA-15。通过IR、TG、SEM和TEM进行表征,并且将负载型介孔分子筛SiW12/SBA-15用于催化α-蒎烯的环氧化反应。研究硅钨酸负载量、催化剂加入量、过氧乙酸与原料摩尔比及SBA-15的焙烧温度对环氧化产物得率的影响。[结果]将硅钨酸负载到SBA-15上并未破坏介孔分子筛的结构,硅钨酸仍保持着Keggin的基本结构。在550℃下焙烧SBA-15,负载量为30%,催化剂用量为2%,CH3COOOH与α-蒎烯的摩尔比为1.2∶1时,α-蒎烯的转化率为99.4%,产物2,3-环氧蒎烷的得率为90.45%。[结论]通过负载法能够制备负载型介孔分子筛SiW12/SBA-15。该催化剂对α-蒎烯的环氧化反应有良好的催化效果。

[ Objective ] The paper aims to prepare SiW12/SBA-15 catalyst and discuss its performance on epoxidation of α-pinene. [ Method ] SBA-15 was obtained by hydrothermal synthesis method with the template P123, then silicotungstic acid modified mesoporous molecular sieve SBA-15 was obtained by impregnation. The infrared spectroscopy （1R）, thermogravimetric analysis （TG）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） were used to characterize the structure of the catalyst. The performance of the catalyst was studied by epoxidation of α-pinene. The influence of roasting temperature and the dosage of silicotungstic acid loaded, the dosage of catalyst and the molar ratio of peroxyacetic and peroxyacetic were discussed. [ Result] The results showed that the conversion rate of α-pinene could reach 99.40%, and yield of 2,3 -epoxypinane was 90.45% when the molar ratio between α-pinene with peracetic acid was 1.2, dosage of SiWJSBA-15 catalyst was 3% （α-pinene）, and dosage of silicotungstic acid was 30%. [ Conclusion] The SiW12/SBA-15 catalyst can be prepared by impregnation and the catalyst has good performance on epoxidation of α-pinene.