Study On The Preparation, Modification And Adsorption Desulfurization Performance Of Metal Organic Framework Material HKUST-1

Automobile fuel,as the vehicle energy,occupies a large proportion in energy structure of China.The sulfur compounds in the oil products are released into the air after combustion,which will seriously pollute the environment and people's health.Therefore,it is very necessary to effectively remove the sulfur compounds in the fuels.As a new type of adsorption material,MOFs is applied to desulfurize due to their unique adsorption characteristics(such as arge specific surface area,high porosity,and easy adjustment of pores).In this paper,the hydrothermal synthesis method was used to synthesize HKUST-1,which was modified by the loading of graphene(GO)and Fe3O4.GO/HKUST-1,Fe3O4/HKUST-1 and Fe3O4/GO/HKUST-1 composites were obtained.The structure and morphology of HKUST-1 composites were characterized by XRD,FT-IR,SEM,N2 adsorption-desorption,TGA and so on.It was found that GO could be uniformly dispersed on HKUST-1,showing a certain wrinkle morphology.At the same time,the proper GO loaded on HKUST-1 contributed to increasing the BET specific surface area and average pore size of the HKUST-1 composites.Fe3O4 spherical structure could be uniformly dispersed on GO/HKUST-1 with a positive octahedral crystal.Fe3O4/GO/HKUST-1 composites had a certain magnetic property,and their ther6al stability was significantly higher than GO/HKUST-1 composites.It was investigated on the adsorptive desulfurization performance(adsorption time,adsorption temperature,oil mass ratio,and regeneration performance)of thiophene(Th),adsorption kinetics,adsorption thermodynamics and adsorption mechanism by ultrasound-assisted static adsorption method.And the adsorbent was applied into FCC gasoline.The experimental results showed that 1.75%GO/HKUST-1 adsorbent had the best adsorption effect on Th.The adsorption capacity was as high as 60.76 mg/g,when the adsorption time was 240 min,the adsorption temperature was 25?,and the mass ratio of oil was 100:1.Further,after using 5 times,the adsorbent had still good desulfurization actibity and good reusability.The process of 1.75%GO/HKUST-1 adsorption for Th conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model.By analyzing the thermodynamic parameters,it was found that the adsorption process of 1.75%GO/HKUST-1 for Th was an autothermally exothermic reaction with reduced degrees of freedom,and there was both physical and chemical adsorption.Adsorption capacity of 1.75%GO/HKUST-1 for FCC gasoline was 39.56 mg/g.The magnetic composite Fe3O4/GO/HKUST-1 could be well recycled.When the adsorption time was 210 min,the adsorption temperature was 35? and the oil mass ratio was 100:1,the adsorption capacity reached 38.21 mg/g.The removal process of Th conformed to the pseudo-second-order kinetic model and the Langmuir isothermal model.By analyzing the thermodynamic parameters,the Gibbs free energy of Fe3O4/GO/HKUST-1 adsorbent at different temperatures was nagative,indicating that the adsorption process proceeded spontaneously.The adsorption enthalpy was nagative,indicating that the adsorption process was exothermic reaction.The adsorption entropy was nagative,indicating that the adsorption process was the process of decreasing the degree of freedom.The process was physical adsorption and chemical adsorption interaction.Fe3O4/HKUST-1 and Fe3O4/GO/HKUST-1 were applied to adsorb the SCC in FCC gasolines,and the adsorbed sulfur capacity was 20.21mg/g and 26.95 mg/g respectively.