Extraction and Stripping of Copper(I) as a Neocuproine Complex in a Surfactant System and Determination of Copper in Steel

Abstract

Abstract An aqueous solution containing surfactants exhibits the property of being separated into two phases due to a temperature change or an addition of salts. The extraction and stripping of copper(I) as a neocuproine complex were investigated between the anionic surfactant of sodium dodecylsulfate (SDS) and aqueous phases. When the surfactant was separated by the addition of NaCl, the copper complex was extracted into the SDS phase. The stripping of copper(I) into the aqueous phase was maintained by phase separation, which was achieved by cooling the solution. Since neocuproine is a highly specific chromogen for copper(I), iron(II) could not form a complex with neocuproine, and was scarcely extracted into the SDS phase. This selective extraction was applied to the separation of copper from iron and the determination of copper in steel samples by a spectrophotometric method and/or an atomic-absorption spectrometric method (AAS).