Closed-vessel microwave leaching of valuable metals from spent lithium-ion batteries (LIBs) using dual-function leaching agent: Ascorbic acid

Abstract A novel closed-vessel microwave system for leaching of valuable metals from spent LIBs was examined using ascorbic acid. Important parameters and energy requirement were assessed. Leaching efficiency Li, Co, Mn total decreased as heating rate increased 5 °C/min to 90 °C/min. significantly with increasing acid concentration. temperature 75 °C 125 °C data fitted well pseudo second order model. Complete obtained at 0.5 M acid, 40 °C/min rate, 10 g/L solid liquid ratio, within 10 min. Using 0.1 M could induce reduction Co (III) in (II), evidenced by XPS analysis. Total 97.66% 58.99% solution recovered on the addition oxalic Compared conventional leaching, provides an effective energy-efficient process since heat loss is lessened high pressure intensified reactions.