China Nonferrous Metallurgy

The bismuth content in the dust of a smelter reaches 2% to 4%, which is not suitable for the use of atomic absorption spectroscopy, hydride generation-atomic fluorescence method and thiourea photometry. However, when the EDTA titration method is used, there are problems such as long time-consuming, narrow titration acidity range (pH 1.5 to 1.7), and difficulty in controlling acidity in the titration process. In this paper, inductively coupled plasma atomic emission spectroscopy (ICP-OES) was used to test the determination of bismuth in copper smelting dust. The sample decomposition method, instrument working conditions, spectral line selection, and matrix effect were analyzed, and the following results were obtained. Adopting a longer cleaning time of the atomization system can overcome the blockage of the atomizer and eliminate the interference; in a 5% nitric acid medium, the antimony content of less than 3% in the sample will not undergo hydrolysis reaction and will not interfere with the determination; use Bi 190.241nm as the analysis line to avoid overlapping with the Cu 223.00nm spectrum line, which can eliminate the interference of copper on bismuth during the measurement process. The recovery rate of bismuth content in the smoke and dust determined by this method is 99.0%~101.1%, the relative standard deviation is 1.51%, and the result is accurate and reliable.