Synthesis Of Fe-MILs Materials And Experimental Study On The Adsorption And Photocatalytic Degradation Of Tetracycline

Recently,Fe-based metal-organic frameworks(MOFs)have attracted increasing attention and been widely used in various fields.To date,however,it is unknown whether they can be employed to degrade tetracycline,one of the most widely used antibiotics,which causing great threats to the environment and human health.This work therefore aims to provide such support by comparing the performance of three Fe-based MOFs(namely,Fe-MIL-101,Fe-MIL-100,and Fe-MIL-53)in removing tetracycline.Firstly,these three materials were prepared by solvent heat method,verify whether they were successfully synthesized by using XRD and SEM analysis,and the three materials were applied to the adsorption and photocatalytic degradation of tetracycline.Experimental results showed that Fe-MIL-101 exhibited the best adsorption performance in tetracycline removal,the adsorption effect of Fe-MIL-100 is the second and Fe-MIL-53 has the worst adsorption effect.In order to analyze the reason of the difference of adsorption effect,BET and FTIR analysis were carried out,and the specific surface area and pore size of the material were compared.Besides,the possible active sites of the adsorption process were analyzed.The thermodynamics and kinetics of Fe-MILs adsorption on tetracycline were analyzed by several models.For the photocatalytic process,after the dark reaction,Fe-MIL-101 removed 96.6%of tetracycline(initial tetracycline concentration at 50 mg/L)while Fe-MIL-100 and Fe-MIL-53 removed 57.4%and 40.6%under the same conditions.Additionally,the effects of adding dosage,irradiation time,and initial concentration of tetracycline on degradation efficiency were examined.It was found that the adsorption and photocatalytic degradation effect was better with the increase of time,the optimum dosage of Fe-MIL-101 was 0.5 g/L and the removal efficiency decreased with the increasing of initial tetracycline concentrations.Moreover,The Fe-MILs was characterized by UV-vis,the visible light absorption threshold and the widths of forbidden band were compared.The trapping experiments and ESR tests indicated that ·O2-,·OH and h+ were the main active species in photocatalytic degradation process of tetracycline.Due to its high removal efficiency and simple synthesis,it could be used as a potential catalyst for degradation of tetracycline and other antibiotics.