乙醇-硫氰酸铵-硫酸铵体系绿色析相萃取分离铟

探讨了乙醇-硫氰酸铵-硫酸铵体系析相萃取分离铟的行为及与一些金属离子分离的条件。结果表明, 硫酸铵能使乙醇水溶液分成两相, 在分相过程中, In³⁺与硫氰酸铵生成的In(SCN)₄^-与质子化乙醇C₂H₅OH₂⁺形成的缔合物[In(SCN)₄^-][C₂H₅OH₂⁺]能被乙醇相完全萃取。当溶液中乙醇、硫氰酸铵和硫酸铵的浓度分别为30%(V/V)、7.0×10^-3 mol/L和0.3 g/mL时, In³⁺的萃取率达到98.1%以上, 而Ce³⁺、Fe²⁺、Cd²⁺、Pb²⁺、Ni²⁺、Mg²⁺、Cr³⁺、Ag⁺、V和Cu²⁺基本不被萃取, 从而实现了In³⁺与上述金属离子的分离。对合成水样中铟的萃取分离和测定, 效果良好。

Green phase extraction separation of indium by ethanol-ammonium thiocyanate-ammonium sulfate system

The extraction of ethanol-ammonium thiocyanate-ammonium sulfate on indium and the separation conditions of some metal elements were discussed. It showed that ammonium sulfate could separate ethyl alcohol into two phases. During phase separation, the In(SCN)₄^- formed by In³⁺ and ammonium thiocyanate reacted with protonated C₂H₅OH₂⁺ and generated complex [In(SCN)₄^-][C₂H₅OH₂⁺] which could be completely extracted with ethanol phase. When the concentration of ethanol, ammonium thiocyanate and ammonium sulfate were 30 % (V/V), 7.0×10^-3 mol/L and 0.3 g/mL, the extraction efficiency of In³⁺ was up to 98.1 %.Ce³⁺, Fe²⁺, Cd²⁺, Pb²⁺, Ni²⁺, Mg²⁺, Cr³⁺, Ag⁺, V and Cu²⁺ were basically not extracted, thus realizing the separation of In³⁺ from the above metal ions. The proposed method had a fine effect on the extraction and determination of indium in water samples.