Simultaneous extraction of palladium and technetium from nitrate solutions with tri-n-octylamine

Abstract

The possibility of simultaneous extraction of palladium and technetium from nitrate solutions was investigated using tri-n-octylamine (TOA) solutions in carbon tetrachloride as a heavy, non-flammable diluent. Conditions of technetium extraction being essentially known, the main attention was focussed on the extraction of palladium which was studied in dependence on the concentration of nitric acid, salts (nitrates, chlorides, nitrites), urea and palladium. A strong decrease of Pd extraction with 10% TOA in CCl₄ has been found above a palladium concentration of 10⁻⁴M but in the presence of chlorides and nitrites a satisfactory high distribution can be preserved. Both Tc and Pd extracted with TOA/CCl₄ can be stripped into dilute ammoniacal solutions. An extraction procedure for the simultaneous isolation of Pd (80% yield) and Tc (99%) from fission product waste solutions (0.20 g Tc and 0.17 g Pd/dm³ 0.5–1.0M HNO₃) is proposed.