Study On Preparation Of Amidoxime-Based Functional Polymer Film And Absorption/Desorption Properties Of Extract Uranium From Seawater

Uranium is a commonly used nuclear fuel and one of the important sources of radioactive contamination.The development of seawater uranium extraction technology can overcome the shortcomings of uneven distribution of terrestrial uranium deposits and improve the energy security of depleted uranium countries.Relevant technologies can be applied to uranium pollution control,which is of great significance.In this paper,the ferrocenyl amidoxime-based functional electrode was prepared by using aluminum sheet as the matrix material,and it was used in the relevant experiments of seawater uranium extraction.Explore the various factors affecting uranium adsorption and the optimal conditions for electrochemical desorption.?1?The polyglycidyl methacrylate?PGMA?was synthesized by free radical polymerization,and PGMA-Fca was prepared by ring-opening reaction of PGMA with ferrocenecarboxylic acid.When n?Fca?:n?PGMA?=0.7,the maximum ring-opening rate was 36%.The cyanoethyl diisocyanate polymer?HNCD?was also synthesized.?2?The optimum hydrolysis pH of KH550 solution(V_KH550:Vwater:V_ethanol=3:92:5) was 9-11,and the conductivity reached the maximum at 12 h after hydrolysis.The self-assembly of KH550 after alkali etching of aluminum sheet was carried out.The optimum assembly time was 60-120 s.?3?HNCD and PGMA-Fca were assembled on the surface of the matrix by layer-by-layer self-assembly.The optimum assembly time of the matrix in 1% HNCD,0.5% PGMA-Fca in DMF solution was 25 min and 15 min,respectively.The electrode was functionalized with 50 g/L hydroxylamine hydrochloride solution,and the optimal reaction time was 50 min at 80?.?4?The effects of adsorption time,pH and adsorption properties of the initial concentration of uranium were investigated.It was found that adsorption equilibrium was reached within 9 h,the optimum pH is 6-7,and the equilibrium adsorption amount is 9.36 mgU·g^-1.Besides,It can be seen from the uranium adsorption isotherm that the initial concentration has a greater influence on the equilibrium adsorption amount.The results of the kinetic equation fitting show that the adsorption of uranium by the functional electrode conforms to the pseudo-second-order kinetic equation.The Langmuir and Freundlich models were used to fit the uranium adsorption isotherm data.The results show that the data accords with the Langmuir model.It is proved that the adsorption of uranium by functional electrodes is mainly strong complexation or chemical adsorption.?5?Cyclic voltammetry was used to characterize the functional electrode in different supporting electrolyte solutions.The results showed that the stability of the functional electrode in phosphate buffer was better than that of 3.5%sodium chloride solution,and the desorption voltage was ?_pc=-0.46 V.