FIBROUS ION EXCHANGERS FIBAN AS SORBENTS OF URANIUM(VI) COMPOUNDS PRESENT IN SULFATE SOLUTIONS

Abstract

Some regularities of Uranium(VI) compounds sorption recovery from model sulfate solutions by fibrous ion exchangers FIBAN C-1 (strongly acidic cation exchanger with -SO3H groups), FIBAN AC-22V (polyampholyte with amino- and carboxyl groups) and FIBAN A-6 (anion exchanger with strongly basic and weakly basic aminogroups) under dynamic conditions were established. It was shown that effective recovery and concentration of Uranium(VI) are combined with a high rate of Uranium(VI) sorption. Quantitative characteristics of Uranium sorption under dynamic conditions such as dynamic exchange capacity, total dynamic exchange capacity, degree of Uranium recovery, Uranium content in the phase of the sorbent, sorption rate were calculated. It was established that the fibrous polyampholyte FIBAN АC-22V demonstrated the better indicators of Uranium(VI) sorption from sulfate solutions and concentration of these solutions (5.2 – 10.5 times) than other fibrous ion exchangers. It was shown that a 10-fold increase in the Uranium concentration in solutions leads to a considerable improvement of the sorption quantitative characteristics. It was found that the initial form of the fibrous ion exchangers can be completely restored by passing through the ion exchangers in Uranium form of a 0.5 M HCl or H2SO4 solutions. It was established that the fibrous polyampholyte FIBAN АC-22V advantageously be used for one cycle of Uranium(VI) sorption – desorption, and the fibrous cation exchanger FIBAN C-1 can be used during two cycles of Uranium(VI) sorption – desorption. The interaction mechanism of the Uranium(VI) compounds present in sulfate solutions (uranyl cations, neutral and negative sulfate complexes) with functional groups of studied sorbents was proposed.