Tannic acid as a novel and green leaching reagent for cobalt and lithium recycling from spent lithium-ion batteries

Abstract Tannic acid–acetic acid is proposed as novel and green chemicals for cobalt lithium recycling from spent lithium-ion batteries through a leaching process. The synergism of both acids was documented batch continuous studies. promotes dissolution by reducing insoluble Co 3+ into soluble 2+ , while acetic critical to improve the stabilize metals in pregnant leach solution. Based on studies, optimum conditions metal recovery at room temperature are 1 M, tannic 20 g/L, pulp density stirring speed 250 rpm (94% 99% recovery). kinetic study shows that increasing 80 °C improves 65 90% (cobalt) (lithium) within 4 h sub-optimum condition (tannic 10 g/L). Kinetic modeling suggests process endothermic, high activation energy indicates surface chemical For other metals, pattern manganese nickel trend follows trend. Copper negatively affected acid. Iron limited due weak acidic solution, which beneficial selectivity.