Metal-Containing Zeolites as Sorbents for Localization of Radioiodine and CsI Aerosols from Vapor-Air and Aqueous Phases

New sorbents for efficient sorption of radioiodine and radiocesium from the vapor-gas phase and aqueous solutions were prepared by treatment of Cu⁺- and Ag⁺-substituted NaX and NaA zeolites with acetylene in aqueous solution. The distribution factor K _d of radioiodine and radiocesium between the modified sorbents and aqueous solutions is higher than 10³-10⁴ ml g^{- 1}. Decontamination factor of the vapor-gas phase with respect to radioiodine and ¹³⁷CsI aerosols exceeds 10²-10³ and 10³, respectively. The sorption properties of the modified sorbents in both aqueous solutions and the vapor-gas phase are better than those of the initial sorbents. However, localization of radioiodine from the vapor-gas phase with the Cu⁺-containing sorbents is less efficient than with the Ag⁺-containing zeolites. At the same time, in aqueous solutions the sorption capacity of the Cu⁺-containing sorbents for radioiodine is appreciably higher than that of the Ag⁺-containing sorbents. The sorption properties of the modified sorbents were studied as influenced by various factors. Paracomplexes of univalent copper and silver with C₂H₂, H₂O, and anions present in the solution are probably formed during modification of the metal-containing zeolites. The dependence of K _d of radioiodine on the metal concentration in the sorbent, the free pore volume of the sorbent, and the anion nature was revealed.