The Preparation Of Loaded Polyacid Catalyst And Its Application In Fuel Oxidation Desulfurization

In recent years,the rapid development of motor industry is not only pushing up economic development but also bring serious problems of pollution,such as haze and acid rain.According to the latest study,the burning of fuel oil is one of the main reasons for the increase of sulfur dioxide emissions in the atmosphere which causes haze and acid rain.For this reason,oil desulfurization has become the important method which will improve the environment.How to resolve deep desulfurization under effective,green and safe conditions has become the key point.In all methods of desulfurization,oxidative desulfurization(ODS)becomes the hot research subject which is researched extensively due to its moderate reaction condition,high efficiency,less equipment invest and low cost.Polyoxometalates(POMs)are a class of transition metal-oxygen clusters with unique properties,which have drawn people's attention in the catalytic field.Heteropoly acid has some unique properties due to its special hierarchical structure.POMs has some unique properties due to its special hierarchical structure,such as,acidity of POMs is stronger than that of inorganic acid,strong oxidizing property,high stability,soluble in polar solvents and good redox potential.These characteristics make it potentially useful in the field of catalysis.Vanadium-substituted Dawson type POMs(H6+n[P2Mo18-nVnO62]·mH2O)was prepared by solvent-extraction method,and characterized by FT-IR?XRD?ICP and Raman.Supported POM catalysts were synthesized with vanadium-substituted Dawson type POMs as active component,with carbon nanotube or hybrid materials as carrier.The structure of catalysts was verified by FT-IR?XRD?N2 adsorb-desorbs,and the morphology and surface chemical composition were investigated by SEM and XPS.Thiophene and dibenzothiophene were used to simulate the sulfide in oil,and two kinds of simulated fuel were prepared.The desulfurization effect of different catalysts on two simulated fuels was investigated under certain conditions,with oxygen in the air as an oxidant.After selecting the optimal catalyst,the different reaction conditions were explored,such as catalyst mass,reaction temperature,oxygen flow,reaction time and stirring rate.The reusability of the catalyst was tested under optimal conditions,and the results show that the catalyst have good reusability.Based on the experimental results,kinetics studies of the oxidative desulfurization are investigated.And the results show that the oxidation reaction of thiophene and benzothiophene follows pseudo first-order reaction kinetics,and the apparent activation energy is calculated through dynamic equation.