负载型碳氧化钼催化剂的制备及其二苯并噻吩的HDS活性

Preparation of γ-Al_2O_3-supported molybdenum oxycarbide catalyst and its HDS activity

通过XRD物相分析和利用小型在线质谱仪,对负载的或体相的氧化钼利用正己烷作为碳源,进行程序升温碳化考察,对所制备的负载型催化剂进行了二苯并噻吩(DBT)加氢脱硫(HDS)活性评价。实验发现,与采用甲烷相比,采用正己烷作为碳源进行碳化可以适当降低碳化所需要的温度,但对于HDS反应来说,并不是碳化越完全催化效果越好。对30%MoO3/-γA l2O3进行碳化时,碳化原料组成为正己烷/氢气=0.025(摩尔比),在620℃碳化1h所得催化剂具有比较好的DBT HDS活性。讨论了制备因素对HDS活性的影响。

Investigation into the temperature programmed reduction （TPR） of bulk or γ-Al2O3 supported molybdenum trioxide using n-hexane as a carbon source in hydrogen was carried out. The resulting catalyst was evaluated using dibenzothiophene （DBT） as a model compound for hydrodesulfurization （HDS）. The results showed that the utilization of n-hexane can lower the temperature, to fulfill carburization to some extent. For DBT HDS, however, there existed an optimal temperature at which carburization was carried out, leading to a high activity of the resulting catalyst. In these experiments, it was found that the resulting catalyst exhibited the highest DBT HDS activity if the precursor, MoO3/γ-Al2O3, with 30% theoretic loading, was carburized at 620℃ under atmospheric pressure and 0. 025 mol ratio of n-hexane to hydrogen in carburizing reagents.