Determination of thallium in high purity selenium

Studies on the analytical methods of trace impurities in high purity substances. VI

Abstract

Chemical analysis of T1 in high purity selenium was studied, whereby the most simple and sensitive method for separation and determination of micro amounts of T1 is established.
Sample is decomposed by nitric acid, sulfuric acid and potassium sulfate, and Se is eliminated by evaporation. The residue is dissolved in hydrobromic acid and T1 is extracted by isopropylether. From the extract, to which is added an aqueous solution of rhodamine B and fully shaken, T1 determined spectrophotometrically.
Determination of T1 down to a content of 0.1 ppm is easily carried out within about 2 hours.