Abstract: Sulfides in diesel oil can be oxidized and then removed by hydrogen peroxide／organic acid system， and the desulphurization rate depends on the system acidity． Inorganic sulfide acid can esaily adjust the system acidity， and thus
improve the desulphurization rate．Benzothiophene was selected as model sulfide and dissolved in n-octane to form model diesel，hydrogen peroxide / formic acid /sulfuric acid were used as the oxidative system．Experiment has been carried out to investigate the catalytic performance of sulfuric acid and the effect of reaction conditions on the oxidative desulphurization rate．The results show that the desulphurization rate can reach to 95% when the molar ratio of hydrogen peroxide to formic acid to sulfuric acid to benzothiophene is 6.4:2．12:1.50:1;The addition of a small amount of sulfuric acid can raise the system acidity and catalyzes the formation of performic acid．Furthermore，the persulphuric acid with stronger oxidativity produced from sulfuric acid also increases the desulphurization rate,and thus increase the desulphurization rate 10%~29%.The amount of sulfuric acid and formic acid，reaction time and temperature had clear effects on the desulphurization rate．Excessive sulfuric acid would result in too strong acidic system which causes the valid decomposing of hydrogen peroxide and thus the reduction of desulphurization rate，and the suitable molar ratio of sulfuric acid to benzothiophene is from 0.30to 2.10．

Key words: Sulfuric acid , Formic acid , Hydrogen peroxide , Oxidative desulphurization , Benzothiophen

摘要： 柴油中的硫化物可以用有机酸催化过氧化氢氧化法脱除，脱硫效率与体系酸性强弱有关。强酸性的硫酸能调节反应体系的酸性，提高脱硫效率。在苯并噻吩/正辛烷配成的模拟柴油中，以过氧化氢/甲酸/硫酸作氧化脱硫体系，考察了硫酸的催化性能以及反应条件对氧化脱硫率的影响。结果表明，在过氧化氢、甲酸、硫酸、苯并噻吩物质的量比为6 .04:2 .12:1 .50:1 .0的条件下，脱硫率可达95%以上；在反应体系中加入微量的硫酸，一方面可以显著增加体系酸性，催化过氧甲酸生成，另一方面硫酸本身参与反应生成具有强氧化性的过二硫酸，从而显著提高体系的反应速率和氧化脱硫率，提高幅度达 10%～29% ；硫酸用量、甲酸用量、反应时间和温度对脱硫率均有影响；过多的硫酸使过氧化氢不稳定，无效分解增加，脱硫率反而下降，硫酸与苯并噻吩最合适的物质的量比在0 .30 ～2 .10。

关键词: 硫酸 , 甲酸 , 过氧化氢 , 氧化脱硫 , 苯并噻吩