Recycling of waste lithium-ion battery cathode materials to synthesize nickel-cobalt-manganese catalysts for efficient CO2 straw gasification

Driven by carbon neutrality goals, the application of carbon dioxide gasification technology has demonstrated significant environmental and economic benefits. This study utilized waste lithium-ion battery cathode materials (LiNi_0.5Co_0.2Mn_0.3, LiCoO₂, LiMn₂O₄) to synthesize highly efficient nickel-cobalt-manganese catalysts for carbon dioxide-assisted straw gasification. Gasification experiments were conducted using a laboratory-scale fixed-bed gasification reactor, and the evolution of the catalyst's structure and physicochemical properties were investigated using characterization methods such as XRD, XPS, SEM, and TGA. The results showed that the catalyst prepared using LiNi_0.5Co_0.2Mn_0.3 as raw material increased the synthesis gas yield to 747.80 mL/g, representing a 134 % increase compared to the control group without catalyst addition; After adjusting the cobalt content to 40 % using LiCoO₂, the synthesis gas yield further increased to 865.24 mL/g, while tar production decreased significantly by 84 % to 4.4 wt%, and activity only declined by 23.3 % after ten cycles. Its outstanding performance stems from the synergistic interaction of Ni, Co, and Mn: nickel promotes carbon dioxide decomposition, cobalt enhances electron conduction, and manganese stabilizes the framework structure. Optimizing cobalt content facilitates C–C bond cleavage and the Boudouard reaction, thereby enhancing tar cracking and carbon monoxide production, and effectively inhibits methane formation through Ni-Co-Mn synergistic reforming. This study establishes a closed-loop “waste battery-catalyst-biomass gasification” strategy, which enables the recycling of waste lithium batteries and the efficient production of synthesis gas, providing a reference for industrial application of high-value utilization of waste lithium batteries and catalytic biomass gasification.