Characterization and beneficiation of pyrolyzed black mass from lithium ion batteries

The lithium-ion battery (LiB) market is growing rapidly. Consequently, LiB wastes will increase in the future and LiB components such as Co, Li, but also graphite, are forecast to be critical materials. These critical materials are contained in the black mass produced by LiBs recycling. This original research focuses on graphite beneficiation from cathode lithium metal oxides by flotation. Detailed characterization of the pyrolyzed black mass (inculding MLA, XRF and XRD) shows that the graphite particles are fully liberated from the copper foils, and the organic layer PVDF is removed. Batch flotation shows that pretreatment, such as attritioning, improves process efficiency while preserving the shape of spheriodized graphite. Concentrate impurities mainly comprise fine particles from cathode active materials, which can be removed with desliming and flotation cleaner stages. As an outlook, this reasearch is expected to bring about an innovative and useful process for the recycling industry.