The International Process Metallurgy Symposium (IPMS2025) hosted by Aalto University, was held on 27–28 October 2025 in Espoo, Finland. Researchers and industry experts gathered to explore how metallurgy can serve as a key enabler of the circular economy. A well-balanced mix of academic and industrial participants discussed sustainable solutions for the recovery and recycling of critical materials, particularly those essential to the energy transition. KU Leuven was represented by Professor Koen Binnemans and the ENICON project by Dr. Brecht Dewulf, who both presented their recent research and perspectives.

Professor Binnemans presented a key-note lecture on “Challenges in Industrial Solvent Extraction Processes for Energy Transition Metals.”, which was based on decades of experience developing continuous countercurrent solvent extraction systems using mixer-settlers and extraction columns applied to real industrial feed solutions (and not synthetic ones). Drawing from direct collaboration with companies implementing solvent extraction in their process flowsheets, professor Binnemans emphasized the practical challenges and operational nuances encountered in large-scale applications.

Dr. Dewulf presented work on the “upgrading of ferronickel to battery-grade nickel”, based on an HCl-based process developed within the ENICON project. The results obtained from countercurrent mixer-settler tests at SOLVOMET’s mini-pilot facilities showed that it was possible to efficiently leach ferronickel and laterite ores, without the need of high temperatures and pressures, hence significantly reducing the carbon footprint of leaching compared to conventional techniques such as high pressure acid leaching (HPAL).  Furthermore, the high removal efficiency of iron from the resulting leach solution enabled the production of a pure Ni/Co solution and mixed hydroxide precipitate, suitable for further processing into battery-grade nickel and cobalt.

In addition to the scientific presentations, several key topics were discussed throughout the symposium. A few highlights include:

• The generation of Na₂SO₄ in many hydrometallurgical flowsheets remains a challenge, calling for innovative solutions to minimize the sulfate and chloride footprints;
• The electrification of hydrometallurgical processes was identified as a promising route toward improved sustainability;
• Sodium-ion batteries are not expected to replace lithium-ion batteries, but rather to serve as a complementary technology.

Overall, the IPMS2025 provided an inspiring platform for dialogue between academia and industry, reinforcing the importance of innovative metallurgical processes in advancing circular and sustainable materials technologies.