SOLVENT EXTRACTION OF PALLADIUM(II) WITH A SULFUR-CONTAINING CARBOXYLIC ACID

Abstract

The mechanism of solvent extraction of palladium (II) from aqueous ammonium chloride solution with α-butylthiolauric acid( α-BTLA = S) in toluene was investigated in terms of extraction equilibrium and kinetics at 303 K. From the results of extraction equilibrium, it was found that α-BTLA behaves as a solvating extractant for palladium(II) and that the extracted species is a 1:2 metal:reagent complex, PdCl₂S₂ The extraction rate of palladium(II) was measured in a batch-type vigorously stirred cell. The effects of the concentrations of palladium(I I), hydrogen ion, chloride ion and extractant on the extraction rate were quantitatively interpreted by a reaction mechanism where the parallel reactions of α-BTLA with PdCl₃(H₂0)- and PdCl₄ ^2- are the rate-determining steps.