Effects of inorganic ligands on the efficiency of ion-exchange treatment of radioactive waste

Normally, liquid radioactive waste contains salts of mineral acids, the concentration of which may exceed the concentration of polyvalent ions of radioactive metals by several orders of magnitude. This, however, does not make improbable the formation of metal cation complexes with acid anions. The effects of inorganic ligands on the sorption characteristics of cations were evaluated by eluting milliquantities of metal (cobalt, magnesium) ions from the sulfocationite phase using sodium salts. The dependences of the time of retention of polyvalent metal ions by the Dowex-50×8 sulfocationate on Leden's function have been studied. It has been proved that ligands of mineral acids are capable to have a pronounced effect on the efficiency of the cation-exchange treatment of solutions. It has been found that the charged complexes formed have a greater effect on the ion exchanger sorption behavior than neutral complexes, despite the fact that the stability constant value of charged complexes is at least an order of magnitude as less as that of neutral complexes.Practical methods have been proposed to minimize the effects of inorganic ligands on the radioactive solution ion-exchange decontamination factor.