Determination of copper in steels by inductively coupled plasma atomic emission spectrometry with gas-phase sample introduction technique

摘要

Copper in steels was determined by inductively coupled plasma atomic emission spectrometry with gas-phase sample introduction in a reaction medium of citric acid. The gaseous copper species, as yet unidentified, was phase-separated in a gas-liquid separator and directed via a stream of argon carrier gas to an inductively coupled plasma for atomic emission spectrometry. Under the optimized experimental conditions, the best attainable detection limit at CuI 324.754nm line was 1.5 ng/ml with a linear dynamic range of 10 to 500ng/ml in concentrations. The presence of several diverse elements was found to cause more or less a depressing interference by the proposed technique. When copper in steels was determined, a large amount of iron in the solution caused a severe depressing interference. Of the extraction solvents examined, diethyl ether was found to be the most preferable to separate iron from copper in the sample solution. The proposed method was applied to the determination of low concentrations of copper in steels. The results obtained by this method were in good agreement with the certified values.