Reductive transformation and synergistic action mechanism in the process of treating spent lithium-ion batteries with antibiotic bacteria residues

Abstract

The rapid development of sustainable energy has led to the production of a large number of spent lithium-ion batteries (LIBs), and the toxic metals in spent LIBs will have an adverse impact on the environment and human health. An environmentally friendly and economical recycling method is essential for resource recycling and environmental management. In this work, “treating waste with waste” is innovatively proposed to realize the high-value utilization of different types of solid waste based on the reduction conversion between antibiotic bacteria residues (ABRs) and spent cathode powder (SCP). The reaction products are primarily transformed into Ni, Co, C, MnO, Li2CO3 and CaO under the optimum conditions of ABRs thermal reduction. Then, the valuable metals can be efficiently recovered by low acid leaching without reducing agent. The recovery efficiencies of Ni, Co, Mn, and Li are 99.4%, 99.5%, 99.9% and 99.9% respectively under the optimum leaching condition of 1.0 mol L−1 H2SO4, L/S ratio of 20:1, reaction temperature of 333 K and reaction time of 60 min. In addition, the acid leaching residue can be directly reutilized as LIBs anode materials, which exhibit excellent electrochemical performance. Comparing with the traditional thermal reduction method, this method has advantages of realizing synergistic treatment of two kinds of wastes simultaneously through one-step heat treatment, efficient recovery of valuable metals with low acid and high value utilization of ABRs. The process of treating waste with waste provides a new direction for the recovery of spent LIBs and the treatment of carbonaceous solid wastes.