微波合成TS-1分子筛的催化性能研究

采用微波加热技术法合成TS-1分子筛, 以30%的H₂O₂水溶液为氧化剂, 考察了所合成的TS-1分子筛在苯乙烯和1-己烯环氧化反应中的催化性能, 并与传统水热法合成的TS-1进行了比较. 结果表明, 由微波合成TS-1的催化性能比传统水热法合成的TS-1更为优异. 采用XRD, FT-IR, UV-vis, SEM等手段对二者进行表征, 发现微波合成的TS-1晶粒与晶粒之间存在“粘连”现象, 这种现象降低了分子筛表面硅羟基含量, 增加了TS-1分子筛的疏水性, 使得分子筛对反应底物苯乙烯和1-己烯的吸附能力增强, 从而导致催化性能显著提高.

Study on the Catalytic Properties of TS-1 Molecular Sieves Synthe-sized under Microwave Irradiation

Titanium silicate-1 (TS-1) was synthesized under microwave irradiation. Their catalytic property was investigated by the epoxidations of styrene and 1-hexene with 30% H2O2 as oxidant, which is better than that of TS-1 synthesized by conventional hydrothermal methods. Characterization of two kinds of TS-1 were carried out by technologies such as XRD, IR, UV-vis and SEM, etc. The crystal particles of TS-1 mo- lecular sieve from microwave irradiation (TS1-MI) were found to exhibit an adhered columnar morphology and less silanol groups than those from the conventional method (TS1-CM). The better catalytic properties of TS1-MI were deduced to be due to its higher hydrophobicity, which comes from the consumption of sur- face silanol groups between TS-1 particles. The higher hydrophobicity of TS1-MI can increase the adsorp- tion capacity leading to a higher catalytic activity.