二苯并噻吩在分散型钼催化剂和原位产生的氢存在下的加氢脱硫Ⅲ.催化剂前身物、硫化氢、一氧化碳和水对反应的影响

摘要

研究了水水/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.结果表明:对硫芴的加氢脱硫反应,在分散型四硫钼酸铵催化剂存在下,原位产生的氢的效果仅比加入的氢气稍好,而在分散型钼酸和磷钼酸催化剂存在下,原位产生的氢远比加入的氢气有效.实验结果还表明:硫化氢能显著提高分散型钼酸和磷钼酸催化剂的加氢脱硫活性,但在分散型四硫钼酸铵催化剂存在下,硫化氢能促进加氢反应而抑制氢解反应.一氧化碳和水均选择性地抑制氢解反应.%The hydrodesulfurization (HDS) of dibenzothiophene (DBT) was investigated using dispersed catalyst precursors molybdic acid (MA), phosphomolybdic acid (PMA), and ammonium tetrathiomolybdate (ATTM). The results indicated that with ATTM catalyst, in situ hydrogen was slightly more active than the externally supplied molecular H2 for HDS of DBT, but is not so active as with MA and PMA catalysts. The experimental results also indicated that H2S has a significant promotional effect on the catalytic activity of MA or PMA catalyst. While the H2 S promoted the hydrogenation pathway, inhibited the hydrogenolysis pathway with ATTM catalyst.Both CO and H2O selectively inhibited the hydrogenolysis route.