Геохімія техногенезу (Aug 2019)
APPLICATION OF COMPOSITE FIBERS WITH THE FERROCYANIDE K-CU LAYER FOR SELECTIVE REMOVAL OF 137CS FROM MULTICOMPONENT SOLUTION
Abstract
The development of selective adsorbents for liquid radioactive waste amount reduction is an actual problem. Composite adsorbents with the active ferrocyanide phase are of particular interest for 137Cs removal from contaminated waters. Polymer fibers are a promising host solid support for the synthesis of composite adsorbents because composite fibers can be synthesized through a one-stage experiment by formation of ferrocyanide layer on the fibers’ surface in a solution (in situ).Composite adsorbent based on polyacrylonitrile fibers was synthesized by in situ formation of the ferricyanide K-Cu layer on the fibers’ surface. This paper presents the experimental data on 137Cs removal from model solutions prepared from distilled water and high-saline solution from Liman Kuyalnik brine.It was found that the synthesized compo-site fibers with ferrocyanide K-Cu layer can effectively remove 137Сs from both solutions. In the case of solution based on distilled water, the adsorption efficiency was 93% and the distribution coefficient – 4,1х103 cm3/g. High selectivity with regard to 137Сs is confirmed by the data on adsorption from the high-saline solution prepared from Liman Kuyalnik brine. In the case of a high concentration of competing sodium and potassium ions in the solution, the adsorption efficiency and distribution coefficient were 99% and 1,9х104 cm3/g, respective-ly.The obtained results are similar to those for the composite polyacrylonitrile fibers with the ferricyanide K-Ni layer, while the composite fibers with the ferricyanide K-Cu layer demonstrate higher adsorption parameters. The synthesized composite fibers can be recommended for the removal of cesium radionuclides from natural and industrial waters, as well as for the decontamination of low-level liquid radioac-tive waste with a high content of competing potassium and sodium ions
Keywords