关键词: 硫酸 , 甲酸 , 过氧化氢 , 氧化脱硫 , 苯并噻吩

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