Synthesis Of TODGA Resin And Its Application For The Simulated Separation Of Am(Ⅲ)

The development and operation of nuclear energy have been producing a large amount of radioactive waste,in which contains a certain number of valuable radionuclides.On the one hand,separating and recovering these isotopes can reduce the radioactivity of waste and facilitate the subsequent disposal;on the other hand,it is of resource and commercial value in reutilizing these radionuclides.Americium（Am）is one of the most concerned radionuclides in radioactive waste,especially in high-level liquid waste（HLLW）.²⁴¹Am,the main isotope of Am,has important applications in radioactive sources and isotope batteries,etc.Therefore,the separation and recovery of Am has certain practical significance and application value.In the present work,two kinds of resin materials with good comprehensive performance were successfully developed for the separation of ²⁴¹Am.Due to the radioactivity and rarety of ²⁴¹Am,a stable element Eu with similar chemical property to Am was chosen as an analogy in the most separation experiments.The extractant TODGA was synthesized by mixed anhydride method.Resin 1（TODGA@SDB）and resin 2（TODGA@Si O₂）were synthesized by one-step polymerization method and physical impregnation method with styrene-divinylbenzene（SDB）and silica（Si O₂）as substrates,respectively.The effect of various factors on the adsorption of Eu（III）by the two resins were comprehensively investigated.Batch adsorption experiments showed that the maximum adsorption capacity of the two resins for Eu（III）is 13.7 mg/g（resin1）and 37.3 mg/g（resin 2）.The adsorption of resin 2 was comparable to that of commercial TODGA resin（commercial 31.6 mg/g）.Both resins showed excellent adsorption performance for Eu（III）in highly acidic environments,with the distribution coefficient（K_d）reaching up to 10⁵ m L/g for resin 2.The two resins exhibited fast adsorption kinetics for Eu（III）,reaching equilibrium within 1 h（resin 1）and 3 minutes（resin 2）.It is also worthnoting that both resins exhibited excellent stability,maintaining their structural integrity and good adsorption performance under extreme conditions such as high-acidy（3 M HNO₃ for 11 days）,high-dose irradiation（200 k Gy）,and high-temperature（200℃）.Meanwhile,in the complex system of multiple coexisting ions,both resins showed good anti-interference ability and selectivity for Eu（III）.In addition,column experiments were conducted to evaluate the practical application potential of the resins.Resin 2 could efficiently capture Eu（III）in the simulated feed solution,and could be eluted by（NH₄）₂C₂O₄ with a recovery ratio close to 95%,indicating a potential for industrial application.Finally,the adsorption behavior of Am（III）on the resin 2 was investigated via trace grade ²⁴³Am.And the results showed a high recovery more than90%.The results of this study may provide valuable approaches and insights for the separation and recovery of Am（Ⅲ）in HLLW.