Study On Lowering The Content Of Sulfur Compounds In FCC Diesel From Nanyang Wax Fine Chemical Plant

By the analysis of the recent domestic and international diesel desulfurizationmethods and the situation of the diesel of Nanyang Wax Fine Chemical Plant, byextensive studies on the sulfur content, sulfur type and desulfurization method of thefluid catalytic cracking (FCC) diesel from Nanyang Wax Fine Chemical Plant, afeasible scheme has been proposed to produce diesel up to grade for Nanyang WaxFine Chemical Plant.According to the analysis of the sulfur types and contents in FCC feedstock, thetransferring mechanism of raw sulfur compounds in FCC unit of Nanyang Wax FineChemical Plant were investigated systematically, including the relationship betweenthe sulfur content of FCC diesel and FCC feedstock, the ratio of the catalyst to oil, thereaction temperature, the freezing point of the diesel, and the effect of currentdesulfurization promoters in FCC unit on lowering the sulfur content of FCC diesel.On the basis of above studies, several schemes have been put forward to reduce thesulfur content of FCC diesel for Nanyang Wax Fine Chemical Plant.Moreover, by the test research of alkli refinery, oxidazied extraction refinery andthe complexation-extraction, by the analysis of the principle of complexation-extraction, this method was successfully applied to the desulfurization of the FCCdiesel from Nanyang Wax Fine Chemical Plant. Through a lot of simulationexperiments, the optimal ratio of solvent to oil, and the optimal dosage of metal areobtained, which has been verified by the experiments of real application. Meanwhileapplication value is verified by the blending analysis of the refined-diesel and diesel,in which all the index attain the standard of the vehicle diesel.Through the studies on the sulfur transferring mechanism in FCC unit, and thecomplexation-extraction refining experiments of FCC diesel desulfurization, anon-hydrodesulfurization method has been proposed in this thesis, which is beneficialto the research of other non-hydrodesulfurization methods.