Application of Microwave Technology on Spent Lithium-Ion Batteries towards Lithium Metal Oxide Recovery Batteries Using Froth Flotation and Magnetic Processes: A Review
Authors: AKINYELE Olabode Samuel , ALABI Oladunni Oyelola , OLORUNTOBA Daniel Toyin , BORODE Joseph Olatunde , OSASONA Babatola , ARAMIDE Fatai Olufemi , Rudolph Martin 
Published: October 2024

The recycling of lithium-ion batteries (LIBs) has become increasingly important due to the rising demand for energy storage solutions and the need to mitigate environmental impacts. Among the valuable materials within spent LIBs, lithium metal oxide is particularly sought after for its role in battery production. This review explores the application of microwave technology in combination with froth flotation and magnetic processes for the recovery of lithium metal oxide from spent LIBs. Microwave technology has emerged as a promising method for LIB recycling due to its ability to selectively heat materials and accelerate chemical reactions. In the context of lithium metal oxide recovery, microwave irradiation offers advantages such as rapid and uniform heating, selective heating of target compounds, and enhanced reaction kinetics. These attributes contribute to reduced processing times, lower energy consumption, and improved recovery efficiency. Froth flotation is a widely used separation technique that exploits differences in surface hydrophobicity to separate minerals. In LIB recycling, froth flotation has been adapted to recover lithium metal oxide from electrode materials. The incorporation of microwave technology into froth flotation processes provides several benefits. Microwaves selectively heat lithium metal oxide particles, facilitating their detachment from the electrode surface and enhancing their recovery. Additionally, microwave-assisted pretreatment promotes the liberation of active materials, leading to increased exposure to flotation reagents and improved recovery rates. Moreover, microwave-assisted froth flotation requires lower temperatures and shorter flotation times, resulting in energy savings and reduced operating costs. Magnetic separation is another method commonly used in LIB recycling to recover magnetic materials such as cobalt and nickel. By exploiting the magnetic properties of these materials, magnetic separation enables their separation from non-magnetic components. Integrating microwave technology into magnetic separation processes offers opportunities for enhanced efficiency and selectivity. Microwave irradiation can assist in the liberation of magnetic materials from electrode materials, promoting their separation. Furthermore, microwave-assisted magnetic separation can operate at lower temperatures and shorter processing times, contributing to energy efficiency and cost-effectiveness. The application of microwave technology in conjunction with froth flotation and magnetic processes shows promise for the efficient recovery of lithium metal oxide from spent LIBs. The synergistic effects of microwave irradiation with these separation techniques lead to improved recovery rates, reduced energy consumption, and lower environmental impact. However, further research is needed to optimize process parameters, scale up operations, and address challenges such as material heterogeneity and equipment design. With continued innovation and collaboration, microwave-assisted recycling processes have the potential to play a significant role in advancing sustainable battery recycling practices.