Potentials and Barriers for Tantalum Recovery from Waste Electric and Electronic Equipment

摘要

Circular economy approaches aim to close material cycles along the value chain. As such, the circular economy can be a long-term strategy to mitigate the risks of critical raw material (CRM) supply. Tantalum, with a current end-of-life recycling rate of less than 1%, has been intermittently discussed as critical. Even though the specificity of tantalum applications and high-mass fractions of tantalum in relevant components provide good boundary conditions, recycling barriers hinder the successful implementation of recycling technologies. With this case study, we identify potentials and barriers for implementing the recovery of CRM, using the example of tantalum. To this end, information about visually identifiable tantalum capacitors (VICs) and printed circuit boards (PCBs) in various equipment types was obtained by disassembly campaigns for mobile phones, smartphones, tablets, notebooks, desktop personal computers, flat screen monitors, servers, etc., and the chemical analyses of resulting fractions. Results show great differences in the application of tantalum in various equipment types. Because of this, the tantalum potential of put-on-market (POM) or of waste electric and electronic equipment (WEEE) devices differs between products and regions. Worldwide, the highest POM tantalum flows originate from desktop computers, but in Germany they originate from notebooks. A focus on particular products leads to higher yields in recycling and supports circular economy approaches. Recycling of tantalum from WEEE is generally possible. But an accurate separation of tantalum from PCBs is not feasible solely by separation of VICs. This process also leads to the loss of silver. Further, this study reveals potential miniaturization trends, decreasing the use of VICs, with an anticipated substitution of tantalum with niobium. These barriers impede long-term recycling strategies for tantalum aimed at establishing a circular economy.