碱金属离子在树脂上的动态吸附行为

Dynamic adsorption of mixed alkali metal ions onto resins

选取4种Na型树脂(D001、D113、Ls-1000、Ls-5000)为吸附剂,通过动态吸附法研究其对碱金属混合溶液的动态吸附行为,重点考察了其中铷、铯的分离性能,并考察了溶液p H、溶液组成、流速及树脂类型等对分离性能的影响。研究发现,中性条件下对铷、铯的吸附量顺序为离子交换树脂>螯合树脂。强酸性树脂D001对碱金属离子的亲和顺序为Cs+>Rb+>K+>Li+,其余3种树脂均为Cs+<Rb+<K+<Li+。吸附液的酸碱度和吸附柱的长径比对分离效果的影响比较明显,流速对分离效果基本无影响。在适宜的条件下,可以实现铷、铯与其他碱金属,以及铷、铯之间的部分或全部分离。

Column dynamic adsorption experiments were carried out using four Na-form resins,including D001, D113, Ls- 1000,and Ls-5000 resins,as the absorbents for extracting Rb and Cs ions from solutions of mixed alkali metal ions.The effects of solution pH,composition in solutions, flow rate, and adsorbent types on the dynamic adsorption performance were investigated.Results showed in neutral solutions, the adsorption amount was found to follow the order of： ion-exchange resins〉 chelating resins.The affinity of alkali metal ions to strong acid-based D001 resin followed the order of： Cs＋〉Rb＋〉K＊〉Li＋, on the contrary, for the other three resins, the order was Cs＋〈Rb＋〈K＋〈Li＋.Solution pH and column length-diameter ratio had obvious effects on the separation efficiency, and flow rate had almost no effects.Under suitable conditions, it was possible to achieve the partial or total separation between Rb, Cs ions and other alkali metal ions, and between Rb and Cs ions themselves.