Stripping Voltammetry with a Flow-through Electrochemical Cell for Simultaneous Trace Determination of Nickel(II) and Copper(II) in Concentrated Alkaline Solutions

Abstract

A highly sensitive method for the on-line simultaneous determination of trace CuII and NiII in high-purity alkaline solutions has been demonstrated by anodic stripping voltammetry (ASV) using a radial flow cell Au electrode (RFCE-Au). In this method, the electrolysis process is performed while alkaline solutions flow through RFCE-Au without any pretreatment. Under the optimum conditions, linear calibration graphs for CuII and NiII were obtained in the range of 0.5-6.0 μg dm−3 in KOH solution and 0.5-5.0 μg dm−3 in NaOH solution, respectively. The detection limits of CuII and NiII, defined as 3 σ of the 0.5 μg dm−3 signal, were 0.047 μg dm−3 and 0.13 μg dm−3 in KOH solution, and 0.058 μg dm−3 and 0.15 μg dm−3 in NaOH solution, respectively. The proposed method is applicable to on-line trace analysis of CuII and NiII, which has been urgently needed in the semiconductor manufacturing process.