Preparation Of Acidic ILs/Zr-MOFs Composites And Its Application In Desulfurization Of Simulated Gasoline

The sulfur compounds in gasoline have a serious toxic effect on the noble metal catalysts in the automobile exhaust purifier,and the combustion to generate SOx is the main source of air pollution,acid rain and photochemical smog,which endangers human health seriously.Therefore,desulfurization of gasoline has become an urgent problem to be solved.Compared with other desulfurization technologies,ODS has the unique advantages of high desulfurization rate,mild reaction conditions,no need for hydrogen,and no influence in octane value of gasoline,which has become the research focus of fuel oil deep desulfurization in recent years.Ionic liquid,as a new generation of non-aqueous solvent,has strong solubility,good thermochemical stability,and its physical properties can be adjusted by the purpose-selected cation and anion and their combination,which is a great advantage for the efficient extraction of sulfide in gasoline.This topic is based on the acidic ionic liquids in gasoline desulfurization remarkable achievement,combining porous material MOFs with large specific surface area,low density,and being able to act as host for a variety of guest molecules.We introduce the acidic ILs into MOFs to form ionic liquid/MOFs composite materials,which reducd the amount of ionic liquid adjust the properties of ILs through the interaction between subject and object.On the basis of ODS,we used ionic liquid/MOFs composite material as catalyst,acetonitrile as extraction agent and H₂O₂ as oxidant to constructe a catalytic oxidation-extraction coupling desulfurization system,in order to achieve higher desulfurization efficiency and the purpose of the catalyst is easy to be recycled.?1?Firstly,we synthesized the carrier material MOF-808 by hydrothermal method.Then acidic ionic liquid[Pr SO₃HMIm]Cl was introduced to the Zr-metal organic framework material MOF-808 by impregnation.We got composite catalyst X%-[Pr SO₃HMIm]Cl@MOF-808?X%=5 wt%,10 wt%,15 wt%,20 wt%?.By means of XRD,FTIR,SEM and EA,it was confirmed that the target carrier material MOF-808 was synthesized and the IL was anchored to the carrier successfully.Based on simulated gasoline as a research object,the desulfurization effect of series catalysts X%-[Pr SO₃HMIm]Cl@MOF-808 was investigated,and it was found that 15 wt%-[Pr SO₃HMIm]Cl@MOF-808 had the best desulfurization performance.The optimum reaction conditions were as follows:catalyst dosage was 15 mg;reaction temperature60?;O/S molar ratio of 25(O/S mole ratio of the oxygen element in the reaction to the sulfur optimal reaction conditions,the desulfurization effect of 15 wt%-[Pr SO₃HMIm]Cl@MOF-808on three kinds of simulated gasoline??Dibenzothiophene?DBT/n-octane,?Benzothiophene?BT/n-octane,?Thiophene?T/n-octane?was DBT>T>BT.The recycling effect of 15 wt%-[Pr SO₃HMIm]Cl@MOF-808 was investigated.After 6 cycles,the desulfurization effect of the catalyst was 97.23%,which only reduced by 0.82%,and the loss of the active component IL was very small,so the activity of the catalyst could be recovered well.?2?By in situ synthesis,a series of composite catalysts X%-[C₂mim]₃PW@Ui O-66?X%=0,0.55 wt%,2.75 wt%,5.5 wt%,11 wt%,16.5 wt%,22 wt%,27.5 wt%?were prepared.When X%=0,it indicated that no heteropoly acid ionic liquid[C₂mim]₃PW was added in the reaction,and the carrier material Ui O-66 was synthesized.By means of XRD,FTIR,SEM and other characterization methods,it was confirmed that the target carrier material Ui O-66 was synthesized and the phosphotungstic acid ionic liquid was successfully anchored to the carrier.Based on simulated gasoline as a research object,the desulfurization effect of a series of catalysts X%-[C₂mim]₃PW@Ui O-66 was investigated,and it was found that 11 wt%-[C₂mim]₃PW@Ui O-66 had the best desulfurization performance,which can achieve 100%.The optimum reaction conditions were as follows:catalyst consumption was 50 mg;reaction temperature 60?;reaction time was 60 min;the molar ratio of O/S is 20;V_extractant:V_{simulated gasoline}=1.Under the determined optimal reaction conditions,the desulfurization effect of the catalyst 11 wt%-[C₂mim]₃PW@Ui O-66 on three kinds of simulated gasoline?DBT/n-octane,BT/n-octane,T/n-octane?was DBT>BT>T.The recycling effect of 11 wt%-[C₂mim]₃PW@Ui O-66 catalyst was investigated.After eight cycles,the desulfurization effect of the catalyst remained above 94%.