Non-destructive approach for upcycling the cathode of spent lithium-ion batteries: Combined with the efficient treatment of organic wastewater

[Display omitted] •A novel strategy of recycling SLIB coupled with organic wastewater treatment.•Pervasive defects and exposed sites in SLIBs greatly facilitate PMS activation.•Nearly 100 % degradation and >90 % mineralization of BAC is achieved within 60 min.•SLIBs show a 1.9-fold increase in the BAC degradation rate compared with fresh Co3O4.•This strategy leads to the ultra-low chemicals and energy consumption. Recycling spent lithium-ion batteries (SLIBs) has been a global research hotspot. However, its low-carbon development has received little attention. Traditional SLIB recycling through hydro/pyrometallurgy is heavily reagent-dependent and energy-consuming, posing high pollution risk. Here, we propose a novel strategy of recycling SLIBs coupling with organic wastewater disposal. Unlike traditional destructive recycling methods, this method takes advantage of the unique characteristics of SLBs such as pervasive defects and active sites to achieve novel utilization. We find that SLIBs show excellent catalytic performances for organic wastewater disposal in the peroxymonosulfate (PMS) activation system. Under optimal conditions of 0.2 g/L catalyst, 2 mM PMS, and initial pH = 7, the degradation rate of benzalkonium chloride exceeds 99 % at 40 min. Importantly, SLIBs also demonstrate efficacy against other typical pollutants, achieving nearly a 99 % degradation rate. The mechanism demonstrates that the redox of Co2+/Co3+ in SLIBs greatly accelerates the generation of reactive oxygen species, where SO4− and 1O2 are the main contributors for the catalytic degradation. In comparison to fresh Co3O4, SLIBs result in a 1.9-fold degradation rate constant. Our findings highlight potentials of recycling SLIBs coupling with other waste disposal and guide high-value utilization of SLIBs in a “treating waste by waste” way.