Printed Circuit Boards (PCB), secondary source of critical metals, are usually recycled to recover precious metals. Alternative routes, aiming to pre-concentrate critical metals, were tested at lab scale. An up-scaling process is proposed involving a thermomechanical separation of PCB and surface mounted devices (SMD). PCB without SMD are treated by solvolysis for desilication and debromination. Further calcination provides a presumably leachable metallic mix. Tantalum capacitors, a specific type of SMD, are treated by pyrolysis, to isolate metallic cores, which are further leached to obtain 92% pure tantalum oxide. LCA data show that tantalum recycling process is profitable for the environment.
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