Semi-empirical equilibrium model for copper(II) extraction from sulphuric acid solution by LIX 64N-Escaid 100

Abstract

A semi-empirical model Y= AK(S F −X) −2X 1+K(S F −X) −2X has been developed to describe the equilibrium relationship for the CuH 2SO 4/LIX 64N-Escaid 100 system. Once the empirical parameters A and K for initial concentration of the organic extraction reagent ( ρ 0) and balance concentration of the acidic species in the aqueous feed ( S F) are available, the equilibrium relationships, with either the same ρ 0 but different S F or the same S F but different ρ 0, can be predicted with satisfactory accuracy. Considerable experimental effort for studying both the effects of ρ 0 and S F on the equilibrium relationship can therefore be saved. Another advantage of this method is that the net rate expression, with a given ratio of the apparent rate constants, can also be obtained. From the value of the parameter AK( S F) −2, which represents the maximum distribution coefficient, one can judge the extraction power of solvent extraction systems.