Circular Potential of Lithium-Ion Battery Recycling Slags: Quantifying Microstructure and Elemental Distribution for...

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Extractive pyrometallurgy is key for lithium-ion battery (LIB) recycling.
• Engineered artificial minerals (EnAMs) can facilitate lithium recovery from slags.
• β-Eucryptite (LiAlSiO₄) is a potential EnAM due to its similarity to spodumene.

Purpose of the Study:

• Quantify lithium content, purity, and microstructure of β-eucryptite in pyrometallurgical slag.
• Assess the viability of β-eucryptite as an engineered artificial mineral for lithium recovery.
• Investigate the co-recovery potential of other valuable elements.

Main Methods:

• Scanning electron microscopy (SEM) for microstructural analysis.
• Electron probe microanalysis (EPMA) for elemental composition.
• Laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) for trace element quantification.

Main Results:

• β-Eucryptite exhibited high lithium content (5.45 wt%) with low iron and calcium impurities.
• Small grain size (< 21 µm) and unfavorable shapes hinder β-eucryptite separation.
• Chromium and vanadium were concentrated in spinel phases, suggesting co-recycling potential.

Conclusions:

• While β-eucryptite shows promise for lithium recovery, its microstructure requires optimization.
• Co-processing of Cr, V-bearing spinel concentrates offers a route for recycling these metals.
• Improved slag quality and byproduct value can be achieved through this integrated approach.