Thiol and thioether removal from RFCC gasoline with attapulgite clay

One of main pollutants in air is sulfur oxides that comes from the combustion of coal and transportation fuels.There are some regulations or rules in many countries,which set the level of sulfur content in transportation fuels,so it becomes urgent to do ultra-deep desulfurization.Hydro-desulfurization process is usually used in petroleum refining industry,in which compounds containing-sulfur are converted to H2S removed in high temperature and high hydrogen pressure.However it is difficult for removing aromatic heterocyclic sulfur.So,alterative technologies have been developed,such as adsorptive-,oxidative-and bio-desulfurization.In this paper a desulfurization agent for residue fluid catalytic cracking gasoline(RFCCG) was prepared by impregnation technique.The compounds of transition metals(Fe,Cu) were used as active component and the attapulgite,treated with nitric acid,as carrier.The sulfur content in RFCCG was analyzed by gas chromatography with atomic emission detection(GC-AED).The desulfurization agent was characterized by fourier transform infrared spectrometer(FTIR),X-ray diffraction(XRD),BET and X-ray photoelectron spectroscopy(XPS).The parameters of desulfurization process for the agent were optimized by experimental study designed by the orthogonal test.The results indicated that the best desulfurization agent obtained are 7% Fe and 6% Cu compounds on attapulgite which was acidulated and roasted at 450℃ for 5 h.The desulfurization rate was 70.02% at atmosphere pressure and room temperature,and sulfur content in RFCCG reduced from 804 μg·g-1 to 241 μg·g-1.