Preparation Of High-Performance Catalysts For Oxidative Desulfurization Of Diesel

The limit of sulfur content of diesel fuel tends to be strict in many countries. So ultra-deep desulfurization of fuel has become an environmentally urgent subject worldwide due to increasing stringent environmental regulations. The traditional hydrodesulfurization(HDS) process needs high equipments investment and operation cost. A number of alternative technologies including adsorption, oxidation, extraction and bioprocessing(ODS) are being explored to realize the ultra-deep desulfurization. Among them, oxidative desulfurization is an effective and promising approach in deep desulfurization of petroleum fractions. An ultra-low sulfur content in engine fuels may be achieved by ODS coupled with the traditional HDS process.ODS usually used H₂O₂ as a oxidant, and the operation is in a batch type. Because H₂O₂ is soluble and need for sufficient mixing. The thesis used cumene hydroperoxide as a oxidation, which is an oil-soluble oxidant. Catalyst is silicon dioxide supported Mo-P ,by the alkali metal modify , ODS activities increase evidently .the reactor is a flow reactor, focuse on research of ODS.The experiment data revealed that MO-P/SiO₂ activity is highter than Mo/Si02. A noteworthy phenomenon is that oxidation activities is increased by modifing. Charaterization by XRD,XRF, Raman, TPR, TPD and UV-Vis revealed that there is a synergistic effect between Mo and P, P in Mo-P/SiO₂ prevent the growth of crystalliized MoO₃, TPD show that acid amount on the surface Mo-P/SiO₂ are more than Mo/SiO₂. modifing can improve activities and selectivity for oxidation of DBT.The sulfur compounds in diesel appeared to be oxidized by GC-MS analysis, after extraction of DMF, the diesel contain less than 1μg/g of sulfur.