Peroxymonosulfate activation by N-doped 3D graphene from spent lithium-ion batteries for organic pollutants degradation: An insight into the degradation mechanism

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-03, Vol.484, p.149379, Article 149379
• Main Authors: Yan, Shuxuan, Chen, Xiangping, Yang, Ying, Zhou, Tao
• Format: Article
• Language: English
• Subjects: Advanced oxidation process; Catalytic mechanism; Nitrogen-doped graphene; Spent lithium-ion batteries; Waste graphite
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2024.149379

Waste graphite from the retired lithium-ion batteries can be designed as peroxymonosulfate activator during reconstruction of porous architecture-based nitrogen-doped graphene using NH3·H2O towards sustainable recycling graphite with significantly upcycling recovery strategy. [Display omitted] •Novel strategy for upcycling spent graphite into high value-added PMS activator.•Lower energy consumption compared to direct high temperature regeneration.•The inherent properties in spent graphite provide an advantage for N doping.•The SNGO-2 exhibits enhanced PMS activation behavior than commercial product.•In-depth chemical reaction mechanism is explored for the activation process. The large-scale retirement of lithium-ion batteries (LIBs) has raised increasing concerns about recycling spent graphite with low value-added. However, it remains challenging to design a low energy consumption and high value-added approach for upcycling spent graphite. This study proposes a novel recycling strategy involving the reconstruction of porous architectures through nitrogen-doped graphene using NH3·H2O to enhance the deactivation resistance of rhodamine B (RhB) degradation via peroxymonosulfate (PMS) activation. Spent graphite with defects and polar functional groups were used as the feed materials. Specifically, the prepared defective nitrogen-doped graphene can efficiently activate the PMS under a broad pH range and a real water matrix. The analytical and density functional theory calculation results suggested that graphite N plays the dominant role in activating PMS with the formation of reactive oxygen species. The quenching, electron paramagnetic resonance and electrochemical results indicated that the singlet oxygen plays a dominant role, while the free radicals of superoxide radical, sulfate radical and hydroxyl radical work together during the degradation of RhB into CO2 and H2O through demethylation, chromophore cleavage, opening-ring and mineralization. This study proposes a promising strategy for upcycling spent graphite from spent LIBs into environmental functional materials with potential application in effluent treatment.