Solvent Extraction Separation of Germanium with Aliquat 336S from Citric Acid Solutions

Germanium was quantitatively extracted with 0.1 mol dm−3 Aliquat 336S in xylene from 1×10−3 mol dm−3 citric acid solution adjusted to pH 3.5. It was stripped with 0.5 mol dm−3 hydrochloric acid and determined spectrophotometrically at 530 nm as the complex with phenylfluorone. It was effectively separated from binary as well as ternary mixtures by taking advantage of the difference in the stability of the citrate complexes with metal ions in mineral acids. The method was applied to the determination of germanium in coal fly ash.