Efficient removal of sulfur and nitrogen compounds from actual fuels by oxidation-extraction process using acids combination

Abstract An effective oxidative system consisting of acids combination followed by an extractive stage were implemented to separate hetero-aromatic hydrocarbons from transportation fuels. N, N-dimethylformamide (DMF) and ethylene glycol (EG) were used as a polar solvent to remove produced compounds from the considered fuel. The impact of operating parameters including temperature, time, oxidizing agent to fuel volumetric-ratio (OFR), fuel to extracting agent volumetric-ratio were studied. Both Sulfur and nitrogen hydrocarbons were reduced considerably in feedstock using H2SO4/HNO3 acid solution after one DMF/EG -cycle under optimal conditions: FSR = 1:1 in one- stage at optimal conditions. OFR = 0.03; T = 50 °C, 400 rpm for 60 min, and total sulfur content is greatly reduced from 96 ppm, 40 ppm, 567 ppm and 1811 ppm to less than 10 ppm for gasoline, kerosene, diesel, respectively, and to 163 ppm for marine diesel, respectively. While, the denitrification efficiencies were 67.57%, 82.14 %, 65.73% and 83.73% for gasoline, kerosene, diesel and marine fuels, respectively. The diesel CG-MS chromatograms reveal that dearomatisation can occur and satisfactory results were obtained.