Acid leaching of LiCoO₂ enhanced by reducing agent. Model formulation and validation

Area of Science:

• Materials Science
• Chemical Engineering
• Hydrometallurgy

Background:

• Lithium cobalt oxide (LiCoO2) is a key material in lithium-ion batteries.
• Efficient recovery of lithium and cobalt from spent batteries is crucial for sustainability.
• Acid leaching is a common method, but complex reactions affect efficiency.

Purpose of the Study:

• To develop and validate a mathematical model for LiCoO2 leaching in acid media.
• To investigate the influence of hydrogen peroxide (H2O2) as a reducing agent.
• To understand the transition between kinetic and diffusion control mechanisms.

Main Methods:

• Formulation of a comprehensive leaching model.
• Incorporation of competing reactions and H2O2 effects.
• Simulation of the leaching process using the developed model.
• Experimental validation with varying HCl and H2O2 concentrations.

Main Results:

• The model accurately simulates Li and Co extraction in the presence and absence of H2O2.
• Simulation results show good agreement with experimental data across various conditions.
• The model predicts a shift from kinetic to diffusion control during leaching.
• The model's predictive capability extends to different solid-liquid ratios and reagent concentrations.

Conclusions:

• The developed model provides a robust tool for understanding and optimizing LiCoO2 leaching.
• It facilitates the design of more efficient and economical metal recovery processes.
• The model's predictive power aids in balancing treatment costs and recovery rates.