Exploratory experimental design for the preparation of[Emim]NTF2/MIL-53(Al)composite and its adsorption performance for hydroxychloroquine sulfate
[Objective]Hydroxychloroquine(HCQ),commonly used as an antimalarial drug and for the treatment of autoimmune diseases,has been detected in surface water and groundwater with low concentrations,posing a significant threat to ecosystems and human health.Therefore,HCQ must be removed from drinking water and wastewater.Among the treatment technologies for HCQ,adsorption has gained considerable attention for its simplicity,low cost,recyclability,and environmental friendliness.However,the relatively low adsorption capacities of reported adsorbents and the long equilibrium time limit their application to the removal of HCQ.Hence,efficient adsorbents with high specific surface areas and adsorption capacities for HCQ must be developed.In this respect,ionic liquids/metal-organic framework(IL/MOF)composites have been regarded as promising adsorbents for organic pollutants because they overcome the disadvantages of ILs and combine the advantages of MOFs and ILs to enhance their adsorption performance for specific pollutants.Hence,this study aimed to evaluate the performance of an IL/MOF composite,namely[Emim]NTF2/MIL-53(Al),for the removal of HCQ from aqueous solutions.[Methods]MIL-53(Al)was prepared using the solvothermal method,and[Emim]NTF2 was introduced into the pores of MIL-53(Al)using the incipient wetness impregnation method to prepare[Emim]NTF2/MIL-53(Al)composites with IL loadings of 10％,20％,and 30％.The structural features of MIL-53(Al)and[Emim]NTF2/MIL-53(Al)composites were evaluated.Batch experiments were designed to explore the HCQ removal performance of MIL-53(Al)and[Emim]NTF2/MIL-53(Al)composites.Then,the impacts of operation factors,including the initial pH value,ionic strength,contact time,HCQ concentration,and adsorption temperature,on the adsorption performance of[Emim]NTF2-20％/MIL-53(Al)were determined.Finally,the adsorption mechanism of[Emim]NTF2-20％/MIL-53(Al)toward HCQ was discussed.[Results]The introduced[Emim]NTF2 greatly enhanced the HCQ adsorption capacities of MIL-53(Al)and the HCQ adsorption capacity of[Emim]NTF2-20％/MIL-53(Al)with an IL loading of 20％was 3.2 times higher than that of MIL-53(Al).The adsorption kinetics were best described by a pseudo-second-order model,and the adsorption process was controlled by layer diffusion and intraparticle diffusion together.The Langmuir model fitted the adsorption isotherms better,suggesting that HCQ molecules were adsorbed onto[Emim]NTF2-20％/MIL-53(Al)in a monolayer manner.Moreover,the thermodynamic analysis revealed that the adsorption of HCQ onto[Emim]NTF2-20％/MIL-53(Al)was exothermic and spontaneous.The adsorption mechanism indicated that the introduced[Emim]NTF2 provided additional adsorption sites through hydrogen bonding and π-π stacking interaction to enhance its HCQ adsorption performance.Compared with other reported adsorbents,[Emim]NTF2-20％/MIL-53(Al)showed a high adsorption capacity of 230.95 mg/g at pH 8.0 and a rapid adsorption equilibrium time of 20 min.[Conclusions][Emim]NTF2/MIL-53(Al)composites were successfully prepared and applied for the effective adsorption of HCQ from aqueous solutions.The introduced[Emim]NTF2 greatly enhanced the HCQ adsorption by providing a hydrogen bond donor and acceptor.Therefore,our research highlights the crucial function of ILs and the potential application of[Emim]NTF2-20％/MIL-53(Al)in the removal of HCQ from aqueous solutions.
NETL
NSTL
万方数据
