Extraction of Ruthenium and Its Separation from Rhodium and Palladium with 4-Pyridone Derivatives

Abstract

Formation of a yellow chelate complex of ruthenium(111) with 3-hydroxy-2-methyl-1-phenyl-4-pyridone or 3-hydroxy-2-methyl-1-(4-tolyl)-4-pyridone in the aqueous phase and extraction of the chelates in dichloromethane were used for spectrophotometric determination of ruthenium. Beer's law was obeyed over the concentration range of 0.1-20.0 mu g cm(-3) ruthenium. Molar absorptivity was 1.35 x 10(4) mol(-1) dm(3) cm(-1) (organic phase, at 393 nm) and 1.29 x 10(4) mol(-1) dm(3) cm(-1) (aqueous phase, at 367 nm), irrespective of the reagent used. The method was successfully applied to the determination of ruthenium in synthetic mixtures. Extraction of a chelate complex of ruthenium(111) with 3-hydroxy-2-methyl-l-phenyl-4-pyridone proved to be a simple and efficacious method for the separation of ruthenium(III) from large amounts of palladium(II) and rhodium(111).