Spectrophotometric determination of scandium using Eriochrome Cyanine R.

Abstract

We have as yet very little information as to the spectrophotometric determination of scandium. {See, this Bulletin, 12, 399 (1963)}. The authors have systematically studied the spectrophotometric behavior of scandium with some triphenyl and azo dyes.
It was found that Eriochrome Cyanine R was one of the most useful reagent for the determination of scandium.
The recommended procedure for the determination is the following ;
To an aliquot of the test solution (1 to 25 μg of Sc) add 2ml of the reagent solution (1% aq. Eriochrome Cyanine R) and 0.1ml of 1.25% gum arabic, and dilute with an ammonium acetate buffer solution (pH 7.2) exactly to 25ml. After 30min. measure the extinction at the wavelength of 535mμ against the reagent solution. The method is suitable for samples containing 0.21.2 ppm of scandium.