Sustainable recycling process for tantalum recovery from printed circuit boards

In IRETA2 project a process to recycle tantalum capacitors from end-of-life printed circuit boards was developed. The process starts with an optical detection of the capacitors followed by capacitors disassembly from both sides of the PCBs within 90 ms using lasers. Both detection and disassembly were integrated into an automated system which takes an average of 2.9 s per capacitor. Furthermore, a refining process was developed to separate the tantalum from the capacitor which includes mechanical treatment, magnetic and density separation, refining electrolysis and thermal oxidation to produce tantalum pentoxide. With the process developed, an overall efficiency for tantalum of at least 73% was achieved. The economic assessment shows that the process is cost-efficient if the market price of tantalum increases by 23 EUR/kg or the process time of optical detection and the laser-based removal reduced by 0.2 s. An environmental LCA demonstrates the ecological benefits of this recycling process compared to primary production.