Don's research interest is hydrometallurgical separation & purification techniques particularly liquid-liquid extraction (LLX), which includes optimization of the current technology and development of new techniques such as electrostatic liquid-liquid extraction (ELX). The emphasis is on their application in the purification of leach solutions from low grade and complex ores such as nickel laterites and rare earths among others, as well as recovery of metals from wastes such as indium, manganese and zinc among others. Following are some specific projects of the research group that he leads:
Development of new LLX techniques such as electrostatic liquid-liquid extraction (ELX). Results generated so far indicate that the technique allows faster mass transfers better control of phase dispersion and lower energy input compared to conventional liquid-liquid extraction.
Control of surface and interfacial precipitation in LLX including, for example, remediation of crud formations in the direct liquid-liquid extraction of nickel and cobalt as well as in the LLX of zinc.
Optimisation of current LLX applications including, for example, impurity control in LLX focusing on the commonly encountered impurities in the purifying of nickel and cobalt from pressure acid-generated (PAL) pregnant liquor stream (PLS) such as calcium, chromium, copper and iron among others.
Recovering metals from wastes such as indium from LCD screens*, manganese and zinc from spent batteries.
*This work is in collaboration with Lappeenranta University of Technology (Professor Erkki Paatero and Sami Virolainen).
