Removal of radioactive iodine from water using Ag2O grafted titanate nanolamina as efficient adsorbent

• Published in: Journal of hazardous materials Vol. 246-247; pp. 199 - 205
• Main Authors: Bo, Arixin, Sarina, Sarina, Zheng, Zhanfeng, Yang, Dongjiang, Liu, Hongwei, Zhu, Huaiyong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.02.2013; Elsevier
• Subjects: Adsorption; Applied sciences; Chemical engineering; Crystallization, leaching, miscellaneous separations; Exact sciences and technology; Iodine - isolation & purification; Iodine Radioisotopes - isolation & purification; Iodine removal; Nanostructures - chemistry; Nuclear waste; Oxides - chemistry; Pollution; Radioactive wastes; Safety; Silver Compounds - chemistry; Titanate nanolamina; Titanium - chemistry; Wastes; Water Pollutants, Chemical - isolation & purification; Titanate nanolamina; Iodine removal; Nuclear waste; Radioactive waste; Similarity; Hazardous waste; Composite material; Adsorption; Surveillance; Morphology; Coherence; Kinetics; Safety; Emergency; Surface area; Surface energy; Interface; Nanocrystal; Iodine
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2012.12.008

► Ag2O nanocrystals were deposited on titanate nanolamina prepared from TiOSO4. ► The composite is efficient adsorbent for removal of radioactive Iodine from water. ► The adsorbent exhibited a high capacity of 3.4mmol of iodine per gram of adsorbent in 1h. ► Ag2O nanocrystals are firmly anchored on the surface of the titanate lamina by coherent interface. ► The adsorbent can be recovered easily for safe disposal and suitable for column adsorption-bed. Emergency treatment of radioactive material leakage and safety disposal of nuclear waste is a constant concern all along with the development of radioactive materials applications. To provide a solution, titanate with large surface area (143m2g−1) and a lamina morphology (the thickness of the lamina is in range of tens of nanometers) was prepared from inorganic titanium compounds by hydrothermal reactions at 433K. Ag2O nanocrystals (5–30nm) were deposited onto the titanate lamina. The surface of the titanate lamina has crystallographic similarity to that of Ag2O nanocrystals. Hence, the deposited Ag2O nanocrystals and titanate substrate join together at these surfaces, forming a well-matched phase coherent interface between them. Such coherence between the two phases reduces the overall energy by minimizing surface energy and anchors the Ag2O nanocrystals firmly on the external surface of the titanate structure. The composite thus obtained was applied as efficient adsorbent to remove radioactive iodine from water (one gram adsorbent can capture up to 3.4mmol of I− anions). The composite adsorbent can be recovered easily for safe disposal. The structure changes of the titanate lamina and the composite adsorbent were monitored by various techniques. The isotherm and kinetics of iodine adsorption, competitive adsorption and column adsorption using the adsorbent were studied to assess its iodine removal abilities. The adsorbent exhibited a capacity as high as 3.4mmol of iodine per gram of adsorbent in 1h. Therefore, Ag2O deposited titanate lamina is an effective adsorbent for removing radioactive iodine from water.