正丙醇-硫氰酸铵-水体系析相萃取分离和富集锗的研究

Study on Enrichment and Extraction of Germanium in 1-PropanolNH_4SCN-H_2O System with Phase Separation

研究了正丙醇-硫氰酸铵-水体系析相萃取分离和富集锗的行为及与一些金属离子分离的条件。结果表明,硫酸铵能使正丙醇的水溶液分成两相,在分相过程中,Ge(Ⅳ)和硫氰酸铵生成的Ge(SCN)62-与质子化正丙醇C3H7OH2+形成的缔合物[Ge(SCN)62-][C3H7OH2+]2能被正丙醇相完全萃取。当正丙醇、硫氰酸铵和硫酸铵的浓度分别为30%(V/V)、5.0×10-2mol/L、0.20 g/mL时,Ge(Ⅳ)的萃取率达到97.0%以上,Cd(Ⅱ)、Ce(Ⅲ)、Mn(Ⅱ)、Pb(Ⅱ)、Cr(Ⅲ)、Al(Ⅲ)、V(Ⅴ)、Ni(Ⅱ)、Ga(III)、Mg(Ⅱ)、Zn(Ⅱ)和Fe(II)基本不被萃取,实现了Ge(Ⅳ)与上述金属离子的分离。对合成水样中锗的分离和测定,结果满意。

The behavior and conditions of enrichment and extraction separation of germanium from other metal ions in 1-propanol-NH4SCN-H20 system with phase separation were studied. The.results showed that 1-propanol aqueous solution could be well divided into two phases in the presence of （NH4）2SO4. The associated [Ge（SCN）6Z- ][-C3 HTOH＋]2 formed with C3 HTOH＋ and Ge（SCN）6^2- （combined from Ge（IV） and NH4SCN） could be completely extracted during this process. Ge（Ⅳ） could be quantiatively separated from Cd（Ⅱ）, Ce（Ⅲ）, Mn（Ⅱ）, Pb（Ⅱ）, Cr（Ⅲ）, Al（Ⅲ）, V（Ⅴ）, Ni（Ⅱ）, Ga（Ⅲ）, Mg（Ⅱ）, Zn（Ⅱ） and Fe （Ⅱ） by extraction, and the extraction percentage of Ge （IV） was over 97.0% when the concentrations of 1-propanol, NH4SCN and （NH4）zSO4 in solution were 30% （V/V）, 5.0 X 10-2 mol/L and 0. 2 g/ mL, respectively. The method has been used for the separation and determination of germanium in water samples with satisfactory results.