The extraction of zinc(II) from chloride solutions by methyltrioctylammonium and methyltridecylammonium chlorides dissolved in chloroform and other diluents and a comparison with Aliquat 336

Abstract

Equilibrium constants for the extraction of zinc(II) from 1.0 and 6.0 M HCl and from 6.0 M LiCl solutions by methyltrioctylammonium and methyltridecylammonium chlorides in chloroform are reported. Vapour phase osmometry studies show that methyltrioctylammonium and methyltridecylammonium chlorides form weak dimers in chloroform and isobutyl methyl ketone. The presence of water in the diluent decreases the extent of dimerization. The aggregation in o-xylene and cyclohexane is more extensive with larger aggregates being formed. The extraction of zinc(II) from 1.0 M HCl by methyltridecylammonium chloride in different diluents follows the order isobutyl methyl ketone > cyclohexane > o-xylene > chloroform. At higher reagent concentrations the effect of aggregation is observed in reversing the order for cyclo- hexane and o-xylene. Anomalous extraction behaviour is observed with isobutyl methyl ketone which may be due to the extraction of a different species in this diluent.