Scandinavia – Researchers at the University of JyvÃ¤skylÃ¤ in Finland have developed a modular approach to the recycling of heterogeneous waste electrical and electronic equipment.
The new recovery process is based on hydrometallurgy, coupled with the electrowinning of copper and modern metal scavenger technologies.
This means that thermally treated e-scrap is leached in stages to separate the metals into the leachates. Copper is recovered via classic electrowinning while noble metals are extracted using a novel liquid method combined with state-of-the-art metal scavengers.
‘We are producing gold, silver, palladium, copper and platinum with very high recovery rates and purities, and rare earth metals as oxides,’ reports project leader Ari VÃ¤isÃ¤nen from the university’s chemistry department.
He began the project three years ago, with support from Finland’s technology industries and from the country’s Sitra innovation fund.
A key aspect of the research project is the capability to analyse critical metals at very low concentration levels, especially from wastewater and fly ash, VÃ¤isÃ¤nen points out. For instance, the researchers have succeeded in identifying individual nanoparticles of silver.
The level of recycling of critical raw materials such as platinum group metals and rare earths is lower than 11% in comparison to their usage, according to the University of JyvÃ¤skylÃ¤.