| At present, oil is the world's most widely used, the largest amount of fuel,its application is mainly reflected in the transport of fuel, such as gasoline,diesel, aviation kerosene and so on. However these fuels have certain sulfides,which are usually present in the form of organic sulfur in fuels such as thiophene thiophene, dibenzo Thienes (dibenzothiophene, DBT) and alkyl substituents thereof. These organic sulfide combustion in the form of SOx emissions to the atmosphere, the atmosphere pollution, a direct impact on human production and living environment. With the increasingly stringent requirements on oil quality in the world, the traditional hydrodesulfurization process (HDS) can remove non-heterocyclic sulfides such as mercaptans and thioethers, but it is difficult to achieve high efficiency and depth for heterocyclic sulfides remove the target. In order to solve this difficulty and challenge, non-hydrodesulfurization (NHDS) came into being. Among them,the oxidation desulfurization (ODS) because of the need for hydrogen, mild conditions, equipment, low investment costs by the people's attention.Schiff is a compound formed by condensation of amines and carbonyl groups, which complex metal ions to form adsorbed alkali metal complexes.Schiff base metal complex has the role of oxygen, can activate molecular oxygen, change its kinetic inert. In a certain temperature range, the rare earth material is a new material with oxygen storage/oxygen release function. Ce02 is a typical rare earth valence metal oxide, with trivalent cerium and tetravalent cerium two valence state, Ce3+ and Ce4+ can be valence state conversion, and therefore has a strong redox capacity. In this paper, CeY was introduced into the sodium sulphate cage of molecular sieves by ion exchange method and NaY molecular sieve as carrier. CeY catalyst was successfully prepared. On the basis of CeY, the cobalt-Schiff base metal complex was encapsulated in the "super cage" of the molecular sieve to prepare the functionalized composite catalytic material with synergistic oxygen storage and oxygenation function. The morphology of the catalyst and the valence state of the active components were characterized by the modern instrumental analysis method, and the performance of the catalyst was tested. The main work is as follows:1?The structure and properties of CeY were characterized by HR-TEM,XRD, XPS, ICP and H2-TPR using the modern instrumental analysis method.The structure and properties of CeY were characterized by ion exchange method. The results show that the catalyst has good structure and morphology when calcined and exchanged at 500 ? for three times. The simulated oil was prepared with n-octane as the solvent and DBT as the target pollutant, and the oxidative desulfurization experiment was carried out with O2 as the oxidant. The results showed that the catalyst had the highest desulfurization effect at the reaction temperature of 100 ?, the ratio of 0.2 g: 25 mL, the concentration of DBT was 200 ppm and the reaction time was 180 min.2?The composite catalyst was prepared by introducing CeY as the carrier, and the coating was prepared by introducing the coating (salen) into Ce-Co(salen)/Y. The materials were characterized by TEM, ICP, XRD and TG-DTA, And under the above conditions for oxidative desulfurization experiments. The results show that the performance of the catalyst is improved after the addition of Co (salen) with CeY as the carrier, which is better than the simple desulfurization effect of Co(salen)/Y catalyst, indicating that the cerium oxide and cobalt Schiff base metal complex There is the effect of synergistic desulfurization. And the catalyst still has a higher desulfurization effect after 10 times of use. |
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