Optimisation of multistage mixer-settler solvent extraction process for the recovery of value metals in leaching of low-grade ores and secondary materials
The demand for elements such as nickel, cobalt, zinc and silver in various applications has increased significantly. Innovation to recover these elements now plays a major role in metallurgical processes as established technologies have challenges in treating available ores while meeting the increasingly stricter environmental regulations. Additionally, secondary sources have become a valuable resource that requires further research. Alternative chloride-based hydrometallurgical processes can be used to recover the value elements from the available feed stocks (primary and secondary) with potentially higher recovery and lower environmental impact.
Solvent extraction (SX) is a process fundamental for the recovery of value elements. Although there is literature on the interfacial tension and its effects on SX performance, there is still a shortage in the understanding on how the selection of the organic phase (extractant, diluent and surfactant) and the operating conditions (pH, electrolyte concentration, temperature) affect the interfacial tension, mass transfer and reaction kinetics at the liquid-liquid interface as well as the coalescence dynamics during the emulsion separation stage. This project aims at expanding this understanding to guide the selection of components and optimise operating conditions to maximize the selectivity and recovery while minimizing residence time for the SX of a given element.