Performance comparison of intensified reactor technologies for the hydrometallurgical separation of cobalt and nickel

Promovendus/a: Jonas Van Olmen

Promotor(en): Prof. dr. ir. Thomas Van Gerven, Prof. dr. Koen Binnemans, De heer Jinu Joseph John

The transition to a low-carbon economy necessitates reliable access to critical raw materials such as cobalt and nickel. While these metals are crucial for making batteries and renewable energy technologies, refining them to the required high purity from ores or secondary sources remains a big challenge. This doctoral project explores better ways to extract these metals using liquids that separate them through a process called solvent extraction. This involves the use of two immiscible liquids to selectively transfer the desired metals from one phase to the other. The study initially tested different chemical systems and extractants, including more novel ionic liquids as well as conventional extraction systems.

Once a suitable model system was obtained, the focus shifted to testing and comparing several advanced reactor designs. These devices help mix the liquids and separate the metals more effectively and with less energy. Investigated designs ranged from mixed vessels to tubular micro-channels that use sound waves to create tiny droplets. The performance of each design was investigated and the power consumption was quantified. All were found to have their own strengths and weaknesses. In the final part of the research, the different reactors were compared in terms of how much liquid they can process per unit of reactor volume, the power consumption per unit of reactor volume and overall amount of cobalt and nickel they can separate.