Deep desulfurization of diesel oil has become an increasingly important subject worldwide due to the upcoming legislative regulations to reduce sulfur content in most countries. Oxidative desulfurization combined with extraction was regarded to be the more promising of new desulfurizataion processes for fuel oil because of the great advantage of a short reaction time, mild reaction conditions and high selectivity.
An amphiphilic catalytic-oxidation system, composed of diesel oil, hydrogen peroxide, and an amphiphilic catalyst [(C₁₆H₃₃) N⁺(CH₃)₃]₃ [PW₁₂O₄₀]^-, combined with extraction has been found suitable for the removal of sulfur in FCC diesel oil. The results demonstrated the amphiphilic catalytic-oxidation system improved the reaction and mass transfer performance and exhibited higher catalytic activity. The optimum oxidation conditions,which were H₂O₂/sulfur molar ratio (H₂O₂/S) of 5, reaction temperature of 80ºC and reaction time of 25min, were obtained. Under the optimum oxidation conditions,combining extraction by γ-butyrolactone,the sulfur removal efficiency and the yield of the oil were 88.1% and 85.0%,respective1y.