Simultaneous Removal of Radioactive Nuclides with Nickel Alginate Microcapsules

Abstract

Nickel alginate microcapsules enclosing inorganic ion-exchangers (ferrocyanide and clmoptilolite) and organic extractant (DEIIPA) were prepared by gelling the kneaded sols. The microcapsules with various shapes such as granule, column and film were easily obtained by changing the gelling methods. The metal ions of Cs⁺, Sr²⁺, Y³⁺, Eu³⁺ and Am³⁺ were readily adsorbed on the microcapsule within 6 h and relatively high uptake percentages above 90 % were obtained. The uptake rate was independent of coexisting NaNO₃ concentration up to 1 M and no appreciable swelling was observed. The uptake of metal ions followed a Langmuir-type adsorption equation and the uptake capacities of C^s+, Sr²⁺, Y³⁺ and Eu³⁺ were estimated to be 0.063, 0.011, 0.051 and 0.149 mmol/g, respectively. The microcapsules were thus effective for the simultaneous removal of radioactive nuclides from waste solutions.