Metals separation by the joint process of facilitated transport and electrodialysis (electromembrane process), employing a liquid membrane compound by D2EHPA–kerosene–formamide

Abstract

Copper separation by an electrically facilitated transport process (EFTP) from a copper, nickel, and iron sulfate salt solution was studied. In the study, a liquid membrane consisting of D2EHPA as the carrier, kerosene as diluent and formamide for conductivity was used, with Nafion as the membrane support. A three-compartment glass reactor was designed for the tests, which consisted of an anodic, a cathodic, and in the middle a liquid membrane compartment. Voltage was applied with platinum electrodes. The effect of pH, current density, electrode area and acid concentration on the extraction of each of the ionic species was determined. Tests were run for 12 h. The best conditions for recovery of copper (96.93%), were 10% D2EHPA, 40% kerosene and 50% formamide. The current density was 0.05 A cm −2. The metal was distributed as follows: 11.20% in the membrane and 85.73% in the cathodic compartment, from which 60.70% was deposited on the cathode and the rest remained in the solution. In conclusion, EFTP is an alternative for copper extraction from multi-ion solutions.