ICP-AES Determination of Potassium, Sodium, Calcium, Magnesium and Sulfate in Carnallite

Sample of carnallite was dissolved in distilled water, an aliquot of the sample solution was taken and used for ICP-AES determination of contents of K, Na, Ca, Mg and SO42-. Spectral lines with wavelengths of 766.5, 330.2, 317.9, 279.8 and 181.9 nm were selected as analytical lines for the determination of K, Na, Ca, Mg and S respectively. Detection limits (3s) found were (mg·L-1) 0.8 (K), 1.6 (Na), 0.8 (Ca), 0.8 (Mg) and 2.4 (S). The proposed method was used in the analysis of sample of carnallite, giving values of recovery of the 5 elements in the range of 97.2%-102.1%and values of RSD′s (n=10) less than 3.5%.