The hydrodesulfurization (HDS) of dibenzothiophene (DBT) in H2O/C6HsCH3 emulsion was investigated using dispersed catalyst precursors molybdic acid (MA), phosphomolybdic acid (PMA), and ammonium tetrathiomolybdate (ATTM).A pseudo-first-order reaction network involving two pathways, direct hydrogenolysis route and hydrogenation route, was proposed. The reaction rate constants in the network were calculated by the optimization method. The model prediction fits well with the experimental data for the nine reaction systems examined. The kinetic data indicated that the hydrogenation route was at least 2 times more rapid than the hydrogenolysis route. The hydrogenation of DBT was 2 times faster than the hydrogenation of biphenyl. The hydrogenolysis of the partially hydrogenated DBT was 1 order of magnitude more rapid than the direct hydrogenolysis of DBT. The calculated results also confirmed kinetic ally that in situ hydrogen was apparently more reactive than the externally supplied molecular H2 for HDS of DBT.%研究了水/甲苯乳化液中二苯并噻吩(硫芴)在分散型钼酸、磷钼酸和四硫代钼酸铵催化剂存在下的加氢脱硫反应.反应在高压釜中于340℃及三种不同的气氛即H2,H2/H2O和CO/H2O(CO和H2O经水煤气转换反应(WGSR)产生原位氢)的存在下进行.用GC和GC-MS鉴定、分析了气体和液体产物的组成.在此基础上,提出了包含直接氢解和加氢脱硫两个反应途径的硫芴加氢反应网络,并采用最优化法计算了反应网络的速率常数.结果表明:对所研究的9个反应体系,反应网络的模型预测值与试验值十分吻合;加氢路径比氢解路径至少快1倍,硫芴的加氢比联苯的加氢快1倍,部分加氢的中间产物1,2,3,4-四氢硫芴和1,2,3,4,10,11-六氢硫芴的氢解比硫芴直接氢解快10倍以上;对硫芴的加氢脱硫反应,在分散型钼存在下,原位产生的氢比加入的氢气更为有效.
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