Coupling the recovery of spent lithium-ion batteries and the treatment of phenol wastewater: A "treating waste with waste" strategy.

The recovery of spent lithium-ion batteries and the treatment of phenol wastewater are both environmental and social issues. In this study, the enhanced recovery of spent lithium-ion batteries and the efficient treatment of phenol wastewater are smartly coupled via a "treating waste with waste" strategy. Under optimal conditions, the leaching process involving phenol achieves 98% and 96% efficiency for Co and Li, respectively. After precipitation, Co and Li could be recovered as Co(OH) 2 and Li 2 CO 3 , and the precipitated Co(OH) 2 was further calcined to generate Co 3 O 4. Furthermore, the organic contaminants that remained in the waste-leaching solution could be removed by a spent graphite-activating peroxymonosulfate (PMS) process. It is noteworthy that the total organic carbon (TOC) in the waste-leaching solution could be removed using fewer PMS compared with the original phenol wastewater owing to the pre-oxidation of phenol during the leaching process, further confirming the advantage of this "treating waste with waste" strategy. Herein, enhanced recovery of valuable metals from spent lithium-ion batteries and efficient treatment of phenol-wastewater are smartly coupled with a 'treating waste with waste' strategy. [Display omitted] • Phenol wastewater is used to enhance the recovery of valuable metals from spent cathode material. • Li and Co have maximum leaching efficiencies of 98% and 96%, respectively. • The organic residues in the waste solution are removed more efficiently by the spent graphite activating PMS process. [ABSTRACT FROM AUTHOR]