Speciation Analysis of Dissolved Copper in Wastewater with Azocarmine B by Light-Absorption Ratio Variation Combined with Continuous Flow Analysis

The sensitive complication between Cu(II) and of azocarmine B (ACB) at pH 6.03 was characterized by the spectral correction method and the complex Cu(ACB)₂ was formed. Because of a good selectivity, this reaction was used for the determination of Cu(II) by the light-absorption ratio variation approach combined with the continuous flow analysis (CFA). The limit of detection of Cu(II) is 0.04 mg/L, the recovery is between 97 and 100% and about 30 samples could be analyzed per hour by CFA. By means of the recommended method, the organic species and inorganic ion species of Cu(II) in two wastewater samples were determined respectively and the former occupies less than 20% of total dissolved Cu(II).