| Recently, people put a lot of attentions to the environmental problems becoming more and more serious. Deep desulfurization of fuel oil has become an environmentally urgent subject worldwide. Very stringent environmental regulations limit the sulfur levels in diesel fuels to less than 15 ppm by the year 2006. However, it is very difficult to decrease the sulfur content from several hundred ppm to a few ppm with traditional hydrodesulphurization (HDS) method. At the same time, strict operation condition and huge instrument investment make cost of oil very high. So alternation and perfection of desulfurization processes are absolutely necessary for producing clean fuels. Possible strategies to realize deep desulfurization currently include adsorption, extraction, oxidation and bioprocesses. Selective catalytic oxidation combined with extraction is one of the most promising deep desulfurization methods. Catalytic oxidation desulfurization may oxide sulfides of fuel oil into sulfones. Then the efficiency of deep desulfurization, by using either extraction or adsorption, can be completed due to the greater polarity and the higher solubility of sulfones in a polar solution than that of corresponding sulfides.Microgel template approaches on the preparation of composite materials with special structure and properties have increased interest in materials science. The main advantage of composite materials is that employing the effect of space confinement of template for guest can easily control the hybridization between template materials and guest with large difference in size as well as the surface morphology of composite microspheres. This research firstly applies the composite microspheres loaded with peroxide phosphotungsten heteropolyacid quarter ammonium salt (PW-HPA) as catalyst to deep desulfurization of fuel oil. The advantages include two aspects. One side, the micrometer size of composite microspheres makes its easy separation from the system possible. The other side, the composite microspheres have hydrophilic core and hydrophobic shell, which can store hydrogen peroxide inside and perform catalysis at the interface.This research mainly focuses on the preparation and characteristic of composite microspheres, and application to deep desulfurization of fuel oil. Based on the idea mentioned above, the research in this thesis includes the following two parts.(1) PAM microgels microspheres were prepared by reverse suspension polymerization technique. The microspheres thus prepared were employed astemplate for the deposition of PW-HPA in the n-heptane and hydrogen peroxide systems, respectively. Then the morphology ^ composition and loading amount of the composite microspheres materials PAM/PW-HPA have been characterized by the SEML FT IR and TGA, respectively.It was demonstrated that the composite materials in shape were generally microspheres with different surface morphology. The surface structures of the composite microspheres could be tailored to certain extent by varying the swelling degree of the PAM template and the amount of PW-HPA deposited. The composite microspheres have micrometer size and nanometer morphology. This characteristic makes its easy separation and big surface possible. So, the preparation method of the composite microspheres is significant in conducting the biphase catalytic microreactor.(2) For a model reaction run, dibenzothiophene (DBT) was dissolved in a mixture of decahydronaphthalene, tetrahydronaphthalene and n-pentane. 30% H2O2 as oxidant and composite microspheres as catalyst oxide the DBT into the corresponding sulfones. Then the mixture is extracted by acetonitrile. Comparing the catalytic performance of PW-HPA and PAM/PW-HPA, the results show that catalytic efficiency of PAM/PW-HPA was almost the same to that of PW-HPA. Under the best condition, the conversion of DBT is about 95%. But the PAM/PW-HPA is separated more easily than PW-HPA from the mixture and can be recycled after dehydrogenization by acetone.
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