Tantalum Capacitor Separation from Waste Printed Circuit Boards with Molten Salt or Metal
Frank Riedewald, Ian M. Povey, Killian Barton, Liam Lewis, Silvia Santos, Maria O'Mahoney, M.J. Sousa-Gallagher
Abstract
Abstract Tantalum is the crucial metal of surface‐mounted (SMD) tantalum capacitors. Some 50 % of the tantalum mined is consumed in its manufacture, making waste printed circuit boards (WPCBs) an excellent source of secondary tantalum. Yet, its recycling rate is less than 1 %. This paper proposes liberating SMD capacitors from WPCBs by treating them with molten metal or salt. For both processes, the epoxy encapsulation of the capacitors did not disengage from the tantalum core. Furthermore, the molten metal process appears superior to the molten salt one. The tantalum capacitors exit the pyrolysis chamber without salt adhering to them.