A study on liquid liquid extraction of cadmium based on KI ethanol in the presence of ammonium sulphate has been performed. It shows that the charged complex compound CdI 2- 4 could be easily extracted into the ethanol phase. Common ions such as Fe 3+ , Co 2+ , Ni 2+ , Mn 2+ , Zn 2+ , Al 3+ and Cr 3+ would not be extracted into the ethanol phase and Cd 2+ could be separated completely from them by mixture of 3.0 g (NH 4) 2SO 4 and 0.2 g KI in 10.0 mL 30%(volume fraction) ethanol solution at pH=1～5.
Mercury ion separation from another metal ions has been carried out in phase system consisted of propanol, NaCl and KI. The results showed that propanol could extract the associates formed by mercury with iodide. Hg(Ⅱ) can be separated completely from Fe(Ⅲ), Co(Ⅱ), Mn(Ⅱ), Mo(Ⅵ) and Zn(Ⅱ) in solution system of pH=2.0.
The behavior of Ammonium sulfate Potassium iodide Ethanol System For Extraction and Separation of Bismuth and the condition of separating of ethanol from water have been study.It shows that as the extracting regent,ethanol,can extract BiI 3- 6.If pH=3～6,Bi(Ⅲ) can be separated from Fe(Ⅲ)、Co(Ⅱ)、Mn(Ⅱ)、Cu(Ⅱ)、 Ni(Ⅱ) 、Mo(Ⅵ).
