Desulfurization of Saudi Arabian crudes by oxidation–extraction method

The oxidation–extraction desulfurization of Saudi Arabian crudes was conducted with hydrogen peroxide–acetic acid oxidation system. The selection of extractant, the optimization of oxidation–extraction conditions, and the exploration of desulfurization mechanism were studied. As DMF was used as the extractant, the optimal desulfurization rate of 35.11 % and oil recovery of 95 % were obtained at 70 °C with the molar ratio of peracetic acid to sulfur of 8:1, the molar ratio of acetic acid to hydrogen peroxide of 2:1 and the volume ratio of extractant to oil of 1:1. The desulfurization effect of different fractions in the treated Saudi Arabian crudes was found to obey the following order: gasoline–diesel fraction >VGO fraction >VR fraction, due to different types and structures of sulfur compounds. The oil quality was less affected and most sulfides were mainly extracted via DMF.