Ti-HMS分子筛的制备与催化氧化脱硫性能研究

以十二胺(DDA)为模板剂，正硅酸乙酯(TEOS)为硅源，于室温下合成了n(SiO2）/n(TiO2)分别为20，40，80，160的中孔杂原子分子筛Ti-HMS，并通过XRD，FT-IR，SEM等物化手段对分子筛进行表征，利用噻吩的催化氧化反应为探针反应来评价所制得样品的催化性能，探索了n(SiO2）/n(TiO2)、反应时间、反应温度对样品催化性能的影响。结果表明：所制备样品具有典型的HMS介孔结构，为大小0.2~0.4 μm的小球。相同的反应条件下，当n(SiO2）/n(TiO2)=20时，噻吩脱除率最高，而n(SiO2）/n(TiO2)=160时，噻吩脱除率比n(SiO2）/n(TiO2)为40和80的分子筛脱硫率高，表明分子筛钛含量和孔径是影响其催化性能的重要因素；在考察范围内，随着反应温度和时间的增长，噻吩脱除率提高。

PREPARATION OF Ti-HMS MOLECULAR SIEVES AND STUDY ON THEIR CATALYTIC OXIDATIVE DESULFURIZATION PREFORMANCE

Ti-HMS mesoporous molecular sieves were prepared at ambient temperature by using neutral dodecylamine (DDA) as template and tetraethyl orthosilicate (TEOS) as silicon source, the n(SiO2)/n(TiO2) of which were 20, 40, 80 and 160. These samples were characterized by XRD, FT-IR, SEM and the catalytic performance of Ti-HMS was evaluated by using catalytic oxidation of thiophene as probe reaction. The influences of n(SiO2)/n(TiO2)，reaction time and reaction temperature on the catalytic performance of these samples were studied. Results showed that the prepared samples had typical HMS mesoporous structure, and with spherical particle size of 0.2-0.4 μm. Under the same reaction conditions, Ti-HMS molecular sieve having n(SiO2)/n(TiO2) of 20 exhibited the highest sulfur removal rate; the sulfur removal rate of Ti-HMS having n(SiO2)/n(TiO2) of 160 was higher than those of samples with n(SiO2)/n(TiO2) of 40 and 80, which indicated that the catalytic activity of Ti-HMS molecular sieve was depended on its Ti content and pore size. Under the testing conditions, with the prolonging of reaction time and the increase of reaction temperature, the sulfur removal rate increased.