Tantalum primary production requires 3987 MJ and generates 262 kg CO -Eq per kg tantalum, while recycling of end-of-life Ta capacitors requires 564 MJ and generates 34 kg CO -Eq per kg tantalum (Schäfer and Schmidt, 2020), highlighting the environmental benefits and importance of tantalum recycling.
Many research groups recovered high-purity tantalum from Ta capacitors. However, waste streams consisting of identical Ta capacitors are only available as new scrap from Ta capacitor production. Instead, the entirety of WEEE and (already) liberated WPCB must be considered as starting material to recycle tantalum from WEEE.
Tantalum capacitors and other components containing or coated with tantalum (such as semi-conductors) are widely used in consumer and communication electronics, medical technology and the automotive industry. Tantalum is a relatively rare metal.
Recycling can help to increase the sustainability of the tantalum supply. Recycling is acknowledged to mitigate environmental impacts, extend the lifetime of resources, reduce geopolitical dependencies and contribute to supply security (Hagelüken, 2013).
Economic aspects are related to supply and demand. The overall demand for tantalum increased steadily since the 1970s (Burt and Schwela, 2013) and future technologies will drive the demand further (Agrawal et al., 2021; Kolotzek et al., 2018; Marscheider-Weidemann et al., 2016).
It is widely applied in telecommunication infrastructure, consumer electronics, vehicles, medical equipment, etc. The sustainable supply of tantalum, however, is at risk, due to rising demand, limited potential for substitution and an uncertain mine production associated with social and environmental implications.