几种汽油脱硫工艺中含硫化合物类型变化规律

SULFUR COMPOUND TYPE DISTRIBUTION IN GASOLINE BY SEVERAL DIFFERENT DESULFURIZATION METHODS

采用气相色谱 -原子发射光谱联用 (GC -AED)技术 ,研究了几种不同的脱硫工艺 (加氢脱硫、吸附脱硫和抽提脱硫 )中各种含硫化合物的变化。加氢脱硫工艺中含硫化合物的脱除效果最好 ,硫脱除率可达 98%以上 ,硫醇、硫醚最易脱除 ,仅有少量的烷基取代噻吩不易被脱除 ,加氢脱硫条件的选择应以汽油中噻吩类化合物的含量而定 ;吸附脱硫工艺中 ,硫醇、硫醚、四氢噻吩类化合物最易脱除 ,受空间位阻的影响 ,取代噻吩比噻吩难脱除 ;在抽提脱硫工艺中 ,因苯并噻吩与所用抽提剂结构相近 ,最易被脱除 ,而空间位阻较大的三甲基噻吩和四甲基噻吩不能被脱除。采用GC -AED技术 ,可根据汽油馏分中含硫化合物的分布来选择合适的脱硫工艺。

The sulfur compound type distribution in gasoling by several different desulfurization methods(hy-drodesulfurization,adsorption desulfurization,solvent extrac-tion desulfurization)has been studied by gas chromatography-atomic emission detectoc(GC-AED).Mercaptan and disulfides were easily removed,only alkylthiophenes were more diffcult to be removed by hydrodesulfurization.Opti-mization of catalyst and operation conditions(temperature,pressure,ratio of hydrogen and oil)depends on the contents of alkyl-thiophene in gasoline with hydrodesulfurization.Sulfur compound types of mercaptan,thioether,and tetrahy-dro-thiophene in gasoline were easily be removed by ad-sorption desulfurization,but disubstiuted thiophene was dif-ficult.For solvent extraction desulfurization,because ben-zothiophene's construction is very similar with the solvent,it therefore was the easiest one to be removed,but ter-and tetra-methyl thiophenes with space hindering property were very difficult to be removed.GC-AED technic is a pro-posed tool for the selection of processes according to sulfur compound type distribution.