Preparation of γ-Al2O3-supported molybdenum oxycarbide catalyst and its HDS activity

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 the hydrodesulfurization (HDS). The results show that the utilization of n-hexane can lower the temperature, to fulfill carburization to some extent. For DBT HDS, however, there exists an optimal temperature at which carburization is carried out, leading to a high activity of the resulting catalyst. In these experiments, it has been found that the resulting catalyst exhibits the highest DBT HDS activity if the precursor, MoO3/γ-Al2O3, with 30% theoretic loading, is carburized at 620°C under atmospheric pressure and 0.025 mol ratio of n-hexane to hydrogen in carburizing reagents.