Solvent extraction of palladium from chloride solutions by alkylammonium di(2-ethylhexyl)dithiophosphates

The extraction of palladium (II) from chloride solutions lover a wide regio n of aqueous acidity) by di(2-ethylhexyl)dithiophosphates of tetraoctylammo nium, tri-n-octylammonium and di-n-octylammonium in toluene at the constant chloride concentration has been studied. A synergistic effect was shown to be observed in these systems and it is explained by the formation of unusu al complexes with mixed ligands. It has been established the palladium comp lexes, such as (R4N)[PdCl(2)A], (R3NH)[PdCl(2)A] and (R2NH2)[PdCl(2)A], inv olving both alkylammonium cation and dialkyldithiophosphate anion are extra cted under conditions of the loaded organic phase using distribution method s depending on a composition of aqueous and organic phases as well spectros copic methods. When the binary extractants are used in an excess, palladium di(2-ethylhexyl)dithiophosphate, PdA(2), is distributed into the organic p hase.