INTERFACIAL ACTIVITY AND RATE OF PALLADIUM(II) EXTRACTION WITH DECYL PYRIDINE MONOCARBOXYLATES

Decyl isonicotiniate and decyl nicotiniate permit a rapid extraction o f palladium(II) from its hydrochloride solutions. Decyl picoliniate is not a suitable extractant. 4-Octylphenylamine can act as a phase tran sfer catalyst when its concentration in the organic phase is at least 2.5 x 10(-4) M. It seems that the interfacial adsorption of pyridine c arboxylates and of 4-octylphenylamine is not the decisive phenomenon i n palladium(II) extraction. The negligible protonation of the pyridine -type extractants and the phase transfer catalysis explains well the q uick extraction of palladium(II) with the commercial and highly hydrop hobic extractant ACORGA CLX-50.