Complexation equilibria between copper(II) and thiosalicylic acid. Spectrophotometric determination of copper in non-ferrous alloys

摘要

The complexation equilibria of Cu(II) with thiosalicylic acid (TSA) have been studied spectrophotometrically in aqueous ethanol (17.08 mol% ethanol) at I = 0.1 M (NaClO4) and 25 +/- 0.1 degrees C. Analysis of the absorbance vs. pH graphs afforded the equilibria in solution and the stability constants of the complexes formed. A simple, rapid, and sensitive method for the spectrophotometric determination of trace amounts of copper is proposed. The effect of interference of a large number of foreign ions was studied. The method has been applied successfully to the analysis of some synthetic mixtures and non-ferrous alloys containing copper.