Preparation Of Functional Film And Study On The Process Of Adsorption-desorption Of Uranium From Seawater

P(Fc-co-AN-co-AA) was synthesized with PAA, PAN and vinylferrocene in the lab; KH-550, PAA and P(Fc-co-AN-co-AA) were coated on the nickel by self-assembly in turn,the coating was reacted with hydroxylamine hydrochloride to make chelating electrode which contained amidoxime-groups, and studied the influence of time and self-assembly film; The process of adsorption-desorption of chelating electrode was studied in the seawater; The electrochemical properties of the electrodes was also studied by cyclic voltammetry, and the conditions of desorption by electrochemical methods was obtained.(1) KH-550 solution was prepared and volume ratio of KH-550, H2O and C2H5OH was 1:1:18, pH was adjusted to 5.5, then the hydrolyzing time was detemined by conductivity meter. It was about 60h in room temperature ;(2) The better dip time of self-assembly film of KH-550, PAA and P(Fc-co-AN-co-AA) was respectively 2 min, 35min and 40min;(3) With chelating electrodes as work electrodes, stainless steel electrodes made in this lab as counter electrodes, calomel electrodes as reference electrodes and NaCl solution(2.8%) as supporting electrolyte, the chelating electrodes performed better electrochemical activities;(4) Oxidation and reduction potential of chelating electrodes was -0.87V and -0.55V in the NaCl solution(2.8%); The oxidation potential was -0.85V, when chelating electrodes adsorbed uranium, and the reduction potentials held the line. So the better condition of desorption were: with stainless steel electrode as counter electrodes, NaCl solution(2.8%) as supporting electrolyte, voltage of desorption was -0.85V; (5) On the chelating electrodes there were two ways to adsorb uranium from seawater, they were electrostatic adsorption and chelating adsorption. The total Freundlich isotherm adsorption equation of absorbing uranium was determined asΓt =2.95×10-5c0.28, and that the equation of electrostatic absorption wasΓe=1.53×10-5c0.33,Γc=1.40×10-5c0.24 for chelated absorption;(6) The influence of temperature on the chelating electrodes to adsorb uranium from seawater could be described by the Arrhenius equation: k=0.11exp(-37.20/RT). Saturation adsorption capacity of the chelating electrodes was determined on the condition of laboratory was 5.6mgU·g-1.