Industrial On-line ICP-OES Analysis of Copper, Cadmium, Cobalt and Iron in Hydrometallurgical Zinc Sulfate Solution

BACKGROUND The determination of impurity elements in hydrometallurgical zinc sulfate solution is helpful to optimize the composition of electrolytes, reduce energy consumption, and accurately feed and improve the purity of smelting metal. Impurity elements in the wet zinc smelting process are usually determined by manual sampling. The sample needs to be diluted before the equipment analysis is performed due to high content of zinc and sulfuric acid, which is difficult to achieve automatic analysis. OBJECTIVES In order to determine the online analysis of impurity elements in the solution of zinc smelting process and meet the current requirements of the hydrometallurgical industry. METHODS An automatic industrial on-line filtration/dilution combined with inductively coupled plasma-optical emission spectrometry (ICP-OES) was used. By optimizing key parameters and selecting appropriate analysis lines, a method for the rapid determination of copper, cadmium, cobalt and iron in zinc smelting solution was developed. RESULTS The experimental results showed that the linear relationship of each element was good, the correlation coefficient was greater than 0.9998, the relative standard deviation was 0.72%-1.39% (n=6), and the spiked recovery was 95%-110%. CONCLUSIONS The factory on-line automatic analysis system can replace traditional manual sampling to achieve automatic analysis. The results of on-line analysis are compared with those of manual sampling in actual production, showing good consistency. This method can be used to fully achieve automatic analysis, simple operation, accurate and reliable results, and is suitable for the analysis of impurity elements in zinc smelting.