【摘要】 催化裂化 (FCC)汽油中的硫化物多以噻吩类硫化物的形式存在 ,而且相对集中在沸程较高的馏分中 .通过固体酸催化剂催化噻吩类硫化物与烯烃的烷基化反应生成多烷基噻吩 ,可较大程度地提高其沸点 ,再经精馏将硫化物转移至FCC汽油的重馏分中 ,从而达到脱硫目的 .考察了AlCl3 CT175树脂催化剂催化模型硫化物如噻吩、2 甲基噻吩及 2 乙基噻吩与异丁烯的烷基化反应性能 ,采用GC FPD和GC MS技术研究了AlCl3 CT175树脂催化剂的失活机理 .结果表明 ,原料中的二烯烃杂质在固体酸催化剂作用下发生聚合反应结焦 ,覆盖在催化剂表面 ,堵塞孔道 ,从而导致催化剂失活 .更多还原

【Abstract】 Over 90% sulfur compounds in FCC gasoline are thiophenic sulfur compounds and most of them exist in the high-boiling fraction. A desulfurization method was proposed for the removal of sulfur compounds from FCC gasoline by alkylation of thiophenic sulfur compounds with olefins over solid acid catalyst, and the obtained alkylated thiophenes were concentrated in the heavy fraction of FCC gasoline by rectification. In this paper, the AlCl 3 catalyst supported on a macroporous sulfonic resin CT175 was used for the alkylation of thiophenic sulfur compounds with olefins, and the deactivation mechanism of the catalyst was studied by means of GC-FPD and GC-MS. The AlCl 3-CT175 resin catalyst showed excellent initial catalytic activity for the alkylation of thiophenic sulfur compounds with olefins in FCC gasoline of boiling range of 60～150 ℃, but the catalyst activity decreased greatly after reaction for 20 h. However, when the liquid feedstock comprising benzene, model sulfur compounds (such as thiophene, 2-methylthiophene and 2-ethylthiophene) and isobutylene was used, the AlCl 3-CT175 resin catalyst showed high stability in the 1*!160 h-duration test, and the conversion of thiophene was higher than 95% under WHSV=2.33 h -1 , isobutylene volume velocity of 7.5 ml/min and reaction temperature of 65 ℃. Meanwhile, the effects of diolefin type (such as isoprene, cyclopentadiene and 5-methyl-1,3-cyclopentadiene) and content on the stability of the AlCl 3-CT175 resin catalyst were further investigated, and the catalyst activity decreased rapidly owing to the fact that the diolefins in the feedstock were polymerized on the catalyst surface.更多还原