离子交换树脂去除模拟放射性废液中的铯

核电站放射性废液组成复杂,其中¹³⁷Cs、⁹⁰Sr和⁶⁰Co是放射性废液处理的主要目标。本文采用稳定同位素模拟放射性废液,研究了Cs^+离子在强酸性阳离子树脂IRN97中的交换等温线、动力学特性以及固定床穿透行为,探讨了共存的硼酸和Sr²⁺、Co²⁺等核素离子对Cs^+离子交换行为的影响。结果表明,废液中存在的高浓度硼酸在一定程度上会减小树脂对Cs^+的交换量;与共存的Sr²⁺和Co²⁺离子相比,虽然Cs^+的交换速率快,但树脂对Sr²⁺和Co²⁺的选择性更高,因此在达到交换平衡状态下,Sr²⁺和Co²⁺的交换容量大于Cs^+;在采用固定床吸附柱进行的动态吸附中,提高Cs^+的进水浓度可以提高树脂的利用率。

Removal of Cesium by Ion Exchange Resins in Simulated Radioactive Wastewater

Radioactive wastewater generated from nuclear power plants is a complex mixture, in which ¹³⁷Cs, ⁹⁰Sr and ⁶⁰Co are main treatment targets in the radioactive wastewater. In this study, simulated radioactive wastewater was used to investigate the adsorption performance of strong acidic cationic resin IRN97 on Cs removal in the aspects of ion exchange isotherms, kinetic properties and penetration behavior. Meanwhile, the effects of boron and other nuclides on Cs⁺ were studied as well. The results show that high concentration boron can reduce the adsorption capacity of Cs⁺. Compared with Sr²⁺ and Co²⁺, Cs⁺ has a higher exchange rate but a lower selectivity. Therefore, the adsorption capacity of Sr²⁺ and Co²⁺ is larger than that of Cs⁺. Increasing the feed concentration of Cs⁺ can enhance the resin utilization factor in the fixed bed adsorption process.