乙醇-盐-水-铜试剂体系萃取分离测定铜。

乙醇-硫酸铵在一定的浓度和比例范围内可以形成两个互不相溶、平衡共存的双水相。对乙醇一硫酸铵双水相的成相条件、Cu（Ⅱ）、Fe（Ⅱ）在体系中的萃取行为进行了初步探讨。实验结果表明，在乙醇浓度为40％，硫酸铵用量为6g，铜试剂加入量为0．5mL，pH=4时铜的萃取率达到最高。并论述了铜铁分离的可能性。

Study on the Aqueous Two-phase System Extraction Separation of Cu with Ethanl-(NH_4)_2SO_4-DDTC System

Ahanol and water can separate two-phase system in the presence of （NH4）2SO4. The extraction behavior of Cu（Ⅱ） Fe （Ⅱ）and condition of phase separation from C2H5OH-H2O solution were studied. Factors influential to the rate were also discussed. It was show that Cu （Ⅱ） was extrated in to C2H5OH with the solution system montioned above while Fe （Ⅱ） was not extracted or extracted at very low rate only, With the amount of Cu was 50 μg, the ethanol was 15 mL Cu （If） could be extracted completey under the amount of （NH4）2SO4 was 6.0 g ,and DDTC （0. 1%） 0. 5 mL pH=4.0. The possibility of separate Cu（Ⅱ）from Fe（Ⅱ） was also disscused.