溴化四丁基铵-碘化钾-水体系中Bi(Ⅲ)与Zr(Ⅳ)、Ce(Ⅲ)、U(Ⅵ)和Mg(Ⅱ)的浮选分离

在水溶液中,Bi(Ⅲ)与溴化四丁基铵和KI形成不溶于水的三元缔合物BiI-4·TBAB+,此三元缔合物沉淀浮于盐水相上层形成界面清晰的液-固两相。当溶液中溴化四丁基铵和KI的浓度分别为5.0×10-4mol/L和3.0×10-3mol/L,pH=3时,Bi(Ⅲ)可与Zr(Ⅳ)、Ce(Ⅲ)、U(Ⅵ)和Mg(Ⅱ)定量分离,Bi(Ⅲ)的浮选率达到100%。对合成水样中Bi(Ⅲ)的分离和测定,效果良好。该方法具有选择性高,操作简便和不污染环境等特点,在微量铋的分离和富集分析中有一定的实用价值。

Study on Floatation Separation of Bi(Ⅲ) from Zr(IV),Ce(Ⅲ),U(VI) and Mg(Ⅱ) with Tetrabutyl Ammonium Bromide-KI-Water System

Bi （ Ⅲ ） combined with tetrabutyl ammonium bromide and KI into a ternary ion association precipitate BiI4^- TBAB^＋ in the aqueous solutions. The precipitate was floated well on the surface of water phase to make the system to divide into both liquid and solid phases with a distinct boundary layer. The Bi （ Ⅲ ） could be quantitatively separated from Zr （ IV ）, Ce （ g ）, U （ VI ） and Mg（ II ） by floatation. And the floatation rate of Bi（ Ⅲ ） achieved 100M when the concentrations of tetrabutyl ammonium bromide and KI in solution （pH= 3） were 5.0 × 10^-4mol/L and 3. 0 × 10^-3 mol/L,respectively. The Bi（ Ⅲ ） in the sample of synthetic water can be separated and determined with satisfactory results. This method is highly selective,easy and can＇t pollute the environment,and certain practical value is expected in separation and enrichment analysis of trace bismuth.