| Sulfur-containing compounds have brought great harm to the naturalenvironment and human life. Therefore, all the countries in the world have adoptedthe very strict sulfur standards, to limit the sulfur content in fuels to ultra low levels.As a result, the research on desulfurization of fuels has become an important researchsubject. The oxidative desulfurization technology has been investigated widely, due tolow investment and high desulfurization rate.Polyoxometalates (POM) as a kind of important oxidation catalysts have alsobeen a lot of applications in the study of oxidation desulfurization. However, the mostof traditional POM are homogeneous catalysts. Although its catalytic activity is good,but the catalyst recovery is difficult. Thus the drawbacks become an important factorto hinder its development and application. To overcome the drawbacks, much recenteffort has been focused on achieving the heterogenization of homogeneous POMcatalysts. Getting efficient, stable heterogenized POM catalysts have become theobjective of the study.Based on the above, in this thesis, the ZrO2supported transition metal substitutedpolyoxometalates catalysts were achieved by sol-gel method (PW11M/ZrO2). By somecharacterization methods, confirmed the transition metal substituted POM weresuccessfully supported on mesoporous ZrO2. POM and the carrier did not changesignificantly in the preparation process. And catalytic performance of the catalyst wasinvestigated through the oxidative desulfurization reaction of thiophene sulfurcompounds with hydrogen peroxide as oxidant. The results indicated that thePW11M/ZrO2are excellent catalytic performance and stability for the desulfurizationreaction of BT or DBT, and the PW11Co/ZrO2is the best catalyst. In addition, to thePW11Co/ZrO2catalyst, the influence of different reaction conditions on thedesulfurization rate has also been studied. Thus, the suitable reaction condition is thatthe reaction temperature is50℃, and the ratio of oxidant to S content is4. |
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