Preparation And Properties Of Antibacterial Materials For Adsorpting And Separating Uranium

The development of clean and efficient seawater uranium extraction materials is a major issue related to the safety and sustainable development of nuclear energy in China in the future.Polymeric uranium adsorption separation materials have the advantages of good physicochemical stability,grafting of multiple functional groups,low cost and preparation into a variety of shapes,which are the closest to large-scale deployment in seawater.2-Methacryloyloxyethyl phosphorylcholine?MPC?is highly hydrophilic and highly selective for uranium adsorption.In this study,atomic transfer radical polymerization?ATRP?was used to graft MPC monomer on the surface of polyvinyl chloride-chlorinated polyvinyl chloride?PVC-CPVC?to obtain the antibacterial uranium adsorption separation material?PVC-PC?.The phase,structure and microstructure of the grafted material were obtained by means of infrared spectroscopy and scanning electron microscopy.The adsorption kinetics,adsorption isotherm and adsorption selectivity of graft materials were investigated by adsorption test.The elution efficiency and reusability of the graft material were tested with sodium carbonate-hydrogen peroxide solution?Na₂CO₃-H₂O₂?.In addition,the antibacterial properties of the materials were tested and analyzed.The main results of this work are as follows:?1?This work successfully grafted PC group on the surface of the substrate through the conventional ATRP method,without damaging the main structure of the material,maintaining the mechanical properties of the substrate well.This convenient one-time chemical grafting method significantly shortened the preparation cycle of uranium adsorption and separation materials.?2?The adsorption capacity of PVC-AO-PC grafted with amine oxime?AO?group and PC group in real seawater with 20 ppm uranium concentration was 8.66 mg U/g-ads.The Na⁺and Al³⁺ions with high concentration and Cd²⁺,Cr²⁺and Cu²⁺used for chelating with AO groups in seawater will affect the adsorption performance of materials.The uranium adsorption capacity of PVC-AO-PC is significantly increased with the increasing grafting degree of PC group,and PC group itself has a good complexation effect on uranium.?3?The adsorption capacity of PVC-PC in 20 ppm uranium solution was up to 373.6 mg U/g-ads,and the adsorption equilibrium state is approximately reached after adsorption for8h.Na₂CO₃-H₂O₂ elution solution can quickly and efficiently elute the uranium complex loaded by PVC-PC.After uranium adsorption/desorption for five cycles,PVC-PC still maintains a high sorption efficiency and elution refficiency.Compared with PVC-AO,PVC-PC showed higher uranium adsorption selectivity,whether alkali metal ions,transition metal ions or lanthanide metal ions.The excellent uranium adsorption and reusability are very important for the practical utilization of uranium extraction in seawater.?4?PC group is not only an excellent uranium binding site,but also endowing graft material with good biocompatibility and excellent resistance to nonspecific protein adsorption can effectively prevent bacteria from attaching to its surface,thus inhibiting the effect of biological contamination on the material.Through the comparison of the plate method,PVC-AO-PC with low degree of PC grafted still showed obvious antibacterial properties.Endowing the antibacterial property of uranium adsorption separation material is an effective method to solve the problem of marine biological fouling.