New vinylpyridine anion exchangers for recovering thorium and nonferrous metals from nitric and hydrochloric acid solutions

Resumo

The ability of new vinylpyridine anion exchangers of AXIONIT VPA series, produced by Axion—Rare and Noble Metals Joint-Stock Company (Russia), to take up Th from nitric acid solutions was studied. The static capacity of the sorbents for Th increases with increasing HNO₃ concentration in the initial solution and reaches a maximum at 7–8 M HNO₃. The sorbed Th can be completely desorbed with dilute HNO₃ solutions. The stability of the sorption characteristics of the ion exchangers in multiple sorption–desorption cycles was evaluated. Vinylpyridine anion exchangers of AXIONIT VPA series well compete in the sorption and kinetic characteristics with VP-1Ap anion exchanger and can be successfully used for recovering Th and Pu from nitric acid solutions. Sorbents of the AXIONIT VPA series also take up copper and cobalt chloride complexes from hydrochloric acid solutions, which allows their use, e.g., for treatment of alkali metal chloride solutions to remove nonferrous metal impurities.