Adsorption of gaseous iodine-131 at high temperatures by silver impregnated alumina

摘要: To prevent radioactive iodides from releasing into the environment in an accident of a nuclear power plant, silver-impregnated alumina (Ag/Al₂O₃) was fabricated, and its performance of radioactive iodine adsorption from high-temperature gas was tested. The silver loadings on alumina were obtained by ICP-OES and the texture properties of Ag/Al₂O₃ were characterized by N₂ adsorption-desorption. The Ag/Al₂O₃ was of reduced specific surface (107.2 m²/g at 650 ℃). Crystalline phases of Ag/Al₂O₃ were confirmed through XRD characterization. After calcination at 650 ℃ for 2 h, the crystalline phase of Ag/Al₂O₃ changed. The ¹³¹I- removal efficiency of Ag/Al₂O₃ was tested at 100, 250, 350, 450 and 650 ℃, with good decontamination factor values for the radioactive iodine. Silver-impregnated alumina can be applied as adsorbents to remove radioactive iodine at high temperatures in nuclear accident.