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Ⅰ.产物分布和反应网络

摘要

研究了水/甲苯乳化液中二苯并噻吩(硫芴,DBT)在分散型钼酸和磷钼酸催化剂存在下的加氢脱硫反应.反应在高压釜中于340℃及经水煤气转换反应(WGSR)产生的原位氢存在下进行.用GC和GC-MS 鉴定、分析了气体和液体产物的组成.结果表明:在反应过程中部分加氢的中间产物1,2,3,4-四氢硫芴(4H-DBT)和1,2,3,4,10,11-六氢硫芴(6H-DBT)的浓度相当高,但二联苯的浓度相对较低,说明加氢路径与氢解路径相当.提出的硫芴加氢脱硫反应网络包含两个反应途径:噻吩环先直接氢解脱硫,紧接着苯环加氢途径;苯环先加氢,然后噻吩环氢解脱硫途径.同时,还包含环烷环的异构化反应.%The hydrodesulfurization (HDS) of dibenzothiophene (DBT) in H2O/C6H5CH3 emulsion was investigated using dispersed catalyst precursors molybdic acid and phosphomolybdic acid. The HDS experiments were performed in an autoclave at 340℃ using in situ generated hydrogen from CO/H2O via the water gas shift reaction. The results indicated that the partially hydrogenated intermediates 1, 2, 3, 4-tetrahydrodibenzothiophene and 1, 2, 3, 4, 10, 11-hexahydrodibenzothiophene were present in quite high concentration, while diphenyl was present in a relatively lower concentration, so the hydrogenation route is comparable to the hydrogenolysis route.A reaction network involving two pathways, direct hydrogenolysis-hydrogenation, and hydrogenation-hydrogenolysis, as well as isomerisation of aliphatic rings was proposed.