Extraction of Scandium Nitrate and Thiocyanate Complexes Using Two-Phase Aqueous Systems and the Determination of Scandium

Resumo

Two-phase aqueous systems, polyethylene glycol PEG-3000 (C₃H₇OH)–NaNO₃ (NaNO₃ + KSCN)–H₂O, are proposed for the selective extraction of scandium nitrate and thiocyanate complexes followed by the complexometric and spectrophotometric determination of scandium. Conditions for analyte separation from rare-earth and concomitant elements are optimized. The procedures are tested on samples of rare-earth metals, concentrates, and an aluminum alloy. The relative standard deviation is not more than 0.8% for complexometric determination and 4.6% for spectrophotometric determination. The time of analysis is not longer than 30 min.