Abstract:The high-value utilization of valuable components in spent lithium iron phosphate has the dual significance of resource recycling and environmental protection. The condition optimization and kinetics of the leaching process were studied for spent lithium iron phosphate electrode powder. The effects of sulfuric acid concentration, reaction temperature, electrode powder particle size and stirring speed on the leaching behavior of Li and Fe were systematically investigated, and the leaching kinetic mechanism of Li and Fe was clarified. The results show that the leaching rate of Li and Fe is above 99.8% under the conditions including sulfuric acid concentration of 2.5 mol/L, leaching temperature of 75 ℃, particle size of 0.14 mm, and stirring speed of 400 r/min. The kinetics indicate that the leaching process is controlled by external diffusion, and the leaching kinetics equation is consistent with Avrami model. The apparent activation energy of Fe and Li during leaching process is 11.03 kJ/mol and 8.45 kJ/mol, respectively. This study l can provide theoretical guidance for simultaneous extraction of valuable elements from spent lithium iron phosphate electrode powder.