1996 Volume 12 Issue 1 Pages 71-75
An X-ray fluorescence method using the coprecipitation-preconcentration technique has been developed for simple determination of both acid-soluble and insoluble trace metal components, such as manganese, iron, nickel, copper and zinc in sea salts. A salt sample is dissolved in a nitric acid solution, and the residue is filtered off onto a membrane filter. After the pH is adjusted to 7-8, the filtrate is boiled, followed by addition of aluminum carrier, oxine and thionalide solutions. The solution is re-adjusted to pH 9, and kept at 80 -85°C for 60min. The precipitates are filtered off onto another membrane filter. X-Ray fluorescence intensities from two filters loaded with the residue and precipitates are measured and the concentrations of the elements are determined simultaneously using the calibration curves. Detection limits were 0.01μg g-1 for manganese and copper, 0.04μg g-1 for nickel and zinc, and 0.05μg g-1 for iron, regardless of the soluble and the insoluble components. The present method was successfully applied to the analysis of sea salt samples.
