| New desulfurization technology of fuel oil had become more attractive for the refinery industry, recently, with increasingly stringent emission standards for gasoline engines. At present the research on the new gasoline desulfurization method is stepped up all over the world, in which oxidative desulfurization (ODS) turns out to be a promising method for its mild reaction conditions, high efficiency, low equipment investment cost, and so on.An amphiphilic catalytic-oxidation/extraction system, using H2O2 as the oxidant, Q+[PW12O40]? as the catalyst, and polar solvent as the extractant, was investigated in this article. The effects of the catalytic-oxidation process and the extraction process on the desulfurization of the model light oil of FCC gasoline were investigated by the experiment respectively.The results on the catalytic-oxidation/extraction desulfurization of model light oil indicated that: when catalyst amount, oxidant amount, oxidized temperature, oxidized time, extracting agent, extract temperature, proportion of oil to solvent were 0.20%, [O]/[S]=5, 50℃, 30min, acetonitrile/water azeotrope, room temperature, 1:1, respectively, the sulfur removal efficiency of the n-heptane/thiophen model light oil can reach above 50%, extension of oxidation time was advantageous to sulfur removal efficiency, the increase removing order of three kind of model sulfide in n-heptane model light oil is: BT >2-ET >Th, enhancement of the oxidized temperature was advantageous to reaction activity, under the identical temperature BT can be removed easier than Th, the increase order of alkane to sulfur removal efficiency was n-hexane > n-heptane > isooctane, the sulfur removal efficiency of extracting agent to model light oil increased in this order: NMP>DMF>BuL>MeCN>MeCN/H2O.The results on catalytic-oxidation/extraction desulfurization of the low sulfur contenting FCC gasoline indicated that: increase of the catalyst amount used to be advantageous in realizing the LS-Oil desulfurization, along with catalyst amount used enlargement, the LS-Oil percentage of desulfurization enhanced, the extension oxidation time influence the desulfurization effected a little, sulfur removal efficiency can enhance as the oxidized temperature improve. Extracting agent was remarkable to the LS-Oil desulfurization effect, sulfur removal efficiency decreased in the order: DMF> methyl cyanide > diglycol /DMF(1:1)>MeCN/H2O> diglycol /DMF (7:3) > diglycol >90% ethyl alcohol >50% methyl alcohol, but the yield of the oil decreased just in the opposite order. The change of extracting agent amount and the extract times were unable simultaneously to guarantee the high sulfur removal efficiency and yield.The results on catalytic-oxidation/extraction desulfurization of the high sulfur contenting FCC gasoline indicated that: when the extraction was carried out as: taking methyl cyanide/water azeotropy as the extracting agent, extract at room temperature, the proportion of oil to solvent at 1:1, vibrates 5min, settles 10min, the effect of the catalyzed oxidation condition can be obtaind. The hydrogen peroxide solution displayed the stronger on the desulfurization than the ammonium persulfate solution. The sulfur removal efficiency increased as the hydrogen peroxide solution amount enhanced. [(C16H33)N+(CH3)3]3[PW12O40] displayed the higher catalytic activity compared to [N+(C4H7)4]3[PW12O40]; The sulfur removal efficiency increased along with the catalyst amount used enhanced, the recycling used catalyst had again with the fresh type suitable catalyzed oxidation activeness, its FT-IR analysis result indicated that this catalyst the structure does not change around the catalyzed oxidation; Extension of oxidation time was advantageous to sulfur removal efficiency. Enhancement of the oxidized temperature was advantageous to reaction activity; with the same oxidant amount used, the catalytic-oxidation system investigated in this article, performed better than the phosphotungstic acid/surface active agent catalytic-oxidation system and the organic acid catalytiv-oxidation system.The catalyic oxidation conditions were as follows : reaction temperature 50℃, reaction time 30min, the amount of hydrogen peroxide [O]/[S]=5(molar ratio), the amount of amphiphilic catalyst 1.25% wt, the result of extraction indicated that: extracting agent was remarkable to the L-Oil desulfurization effect. Compared with the extraction without catalytic-oxidation, the catalytic-oxidation/extraction was more advantageous to the desulfurization. The polarity of extractant is closely related with its desulfurization ability, NMP, methyl alcohol, ethyl alcohol can mix with the gasoline dissolve, sulfur removal efficiency decreased in the order: DMF>BuL> MeCN >DiG, while the yield of oil decreased in the order: DiG>BuL> MeCN >DMF; The water can improved the yield of L-Oil in the extraction system, the amount of water in extractant increased, the yield of L-Oil increased, but the sulfur removal efficiency reduced. The sulfur removal efficiency increased along with the extracting agent amount used enhanced, by contrary the yield reduced. The sulfur removal efficiency increased, and the yield reduced following the increasing the extract times. The change of extracting agent amount and the extract times were unable simultaneously to guarantee the high sulfur removal efficiency and yield. The extract duration of oscillation and the settlement time have certain influence to the desulfurization effect. The extracting agent may carry on the recycling through the simple fractionation, but the desulfhurization effect changed, the yield rate enhancement, while the sulfur removal efficiency reduced.The GC-FPD chormatograph of HS-Oil indicated: this catalytic-oxidation/ extraction system may do effective in removing sulfur-compound in the oil. The FT-IR analysis result indicated: after amphiphilic catalytic-oxidation, sulfide in the gasoline can be oxidized into the corresponding sulphone or the sulphoxide.
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