The increasing amount of electronics, such as consumer products and green technologies, increases the demand of critical metals such as indium and gallium. TNO develops technological solutions to recover indium and gallium from Waste of Electrical and Electronic Equipment (WEEE), so called urban mining. TNO offers possibilities for closing the material loop within the electronics industry thus reducing dependency of primary resources.
Indium and/or gallium can be found in LCD/LED television screens and thin film (CIGS) photovoltaic panels. Indium and gallium are currently not or barely recycled from electronic waste. Our research on the recovery of indium and gallium is focused on hydrometallurgical principles, which involves leaching, concentration, purification and electrowinning. Evaluation of conventional and innovative technologies and their interconnectivity aids the development of an optimal process strategy. The research is performed within the RECLAIM project which is funded through the European Commission’s 7th Framework Programme.
TNO has built up knowledge of membrane technology, hydrometallurgy and electrochemistry which will be used to evaluate leaching, nanofiltration, precipitation, adsorption, extraction and electrowinning processes.
The results of these studies enables development of certain recovery strategies with a focus on reduced chemical and water usage thus providing a more sustainable solution. These recovery strategies will be subjected to a techno-economical evaluation followed by piloting and demonstration on location.
TNO has already developed and demonstrated technology based on supported liquid membranes, so called slug flow pertraction technology (SPT) and is investigating the application of SPT for the selective recovery of indium and gallium. Furthermore, TNO is investigating the production of indium and gallium as pure metal by electrochemistry.