孤岛减压渣油加氢处理过程中硫类型的变化

CHANGES OF MAJOR FORMS OF SULFUR IN HYDRODESULFURIZATION OF GUDAO VACUUM RESIDUE

孤岛减压渣油加氢脱硫后所得残渣油（＞５００℃）的化学组成与原料渣油明显不同，饱和分、轻芳烃、中芳烃显著增加，饱和分与芳烃占８３％，而原料渣油中这两个组分仅占４１％。加氢残渣油的硫含量远低于原料的硫含量，残余硫主要集中在重胶质和沥青质中，且主要是硫醚硫，其中脂硫醚硫约占一半，说明在高压加氢条件下，渣油中噻吩类化合物的主要脱硫途径是先加氢生成相应的硫醚，然后进一步氢解脱硫。

A comparative study on chemical composition,especially the major forms of sulfur,has been conducted for Gudao vacuum residue(VR) and its VRDS vacuum residue in order to illustrate effects of hydrodesulfurization on the changes of major forms of sulfur in the residues The results show that Gudao VRDS VR has very low sulfur content,0 27%,much less than its feed′s sulfur content,2 47%;the sulfur is mainly concentrated in resin and asphaltene fractions of the VR and almost made up of sulfidic sulfur,of which paraffinic sulfidic sulfur accounts for half part In other word,the rest part is ascribed to aromatic sulfidic sulfur,leaving thiophenic sulfur only a minor part From those mentioned above,it can be infered that desulfurization of thiophenic sulfur in VR must have undergone the following two steps:first,hydrogenation of thiophenic rings to related sulfides,then,hydrogenolysis of the sulfides to hydrogen sulfide The direct hydrogenolysis of thiophenic sulfur would not be major reaction during VRDS process