The mechanism of extraction of iron(III) from 6 M hydrochloric acid by long chain amines in chloroform

Abstract

The mechanism of transfer of Fe^llI between 6.0 M HCl and five amine chlorides in chloroform has been studied by means of the single-drop technique. It is suggested that the (1,1) complex forms at the interface by fast ion-exchange and that the rate determining step involves the replacement of the complex at the interface by one molecule of reagent monomer from the bulk organic phase. Additional heterogeneous aggregates are formed in the bulk organic phase by fast reactions with reagent monomer.

Support for this mechanism is obtained through the excellent agreement between the extraction equilibrium constants calculated from the rate data for the (1,1) complexes and the values obtained previously by two phase titration studies.