Solvent Extraction of Copper from Nitrate Media with Chelating LIX‐Reagents: Comparative Equilibrium Study

Abstract

Comparative experimental studies were carried out on extraction of copper(II) cations from aqueous acid nitrate media using four LIX‐reagents, representatives of different extractant classes: LIX 984N‐I, LIX 860N, LIX 84‐I and LIX 65N. As a diluent, liquid hydrocarbon undecane was used. The extraction behavior of the LIX‐reagents was compared based on an analysis of the influence of the main factors on the two‐phase mass transfer process: aqueous pH‐value, initial copper and extractant concentrations, and temperature. The experimental data received were used in the calculation of important parameters characterizing the efficiency of copper extraction from nitrate media with different LIX reagents: distribution ratios D, concentration extraction constants K _ex, pH_0.5‐values, and thermodynamic parameters such as enthalpy, entropy, and free energy changes (ΔH ⁰, ΔS ⁰, ΔG ⁰‐values).

Keywords:

• Solvent extraction
• LIX reagents
• extraction equilibrium
• copper
• water purification