PRECONCENTRATION OF TRACES OF TIN BY COPRECIPITATION WITH YTTRIUM HYDROXIDE FOR ELECTROTHERMAL ATOMIZATION ATOMIC-ABSORPTION SPECTROMETRY

Trace amounts of tin were concentrated by coprecipitation and determined by electrothermal atomisation atomic absorption spectrometry. Yttrium hydroxide coprecipitated quantitatively 0.1 - 3-mu-g of tin from 50-500 ml of sample solution at pH 9.5-11.2. The atomic absorbance of tin increased about twice by using an impregnated graphite tube with yttrium. The impregnated graphite tube, furthermore, improved the reproducibility of the measurement of tin. A linear calibration graph was obtained in the range of 0.004-0.12-mu-g/ml of tin. Twenty-three foreign ions did not interfere seriously. The method was applicable to the determination of tin in zinc metal.