The global market of lithium-ion batteries (LIB) has been growing in recent years, mainly owed to electromobility The global LIB market is forecasted to amount to $1293 billion in 2027 Considering the global reserves needed to produce these batteries and their limited lifetime, efficient recycling processes for secondary sources are mandatory A selective process for Li recycling from LIB black mass is described Depending on the process parameters Li was recovered almost quantitatively by the COOL-Process making use of the selective leaching properties of supercritical CO2/water Optimization of this direct carbonization process was carried out by a design of experiments (DOE) using a 33 Box-Behnken design Optimal reaction conditions were 230 °C, 4 h, and a water:black mass ratio of 90 mL/g, yielding 986 ± 019 wt% Li Almost quantitative yield (9905 ± 064 wt%), yet at the expense of higher energy consumption, was obtained with 230 °C, 4 h, and a water:black mass ratio of 120 mL/g Mainly Li and Al were mobilized, which allows for selectively precipitating Li2CO3 in battery grade-quality (>998 wt%) without the need for further refining Valuable metals, such as Co, Cu, Fe, Ni, and Mn, remained in the solid residue (977 wt%), from where they are recovered by established processes Housing materials were separated mechanically, thus recycling LIB without residues This holistic zero waste-approach allows for recovering the critical raw material Li from both primary and secondary sources

https://www.mdpi.com/2075-4701/11/2/259/pdf

The COOL-Process—A Selective Approach for Recycling Lithium Batteries

Experimental work has been performed to investigate the precipitation mechanism of aluminum hydroxide phases from sodium aluminate/sodium carbonate pregnant solutions by carbon dioxide gas purging. Such solutions result from leaching calcium aluminate slags with sodium carbonate solutions, in accordance with the Pedersen process, which is an alternative process for alumina production. The concentration of carbonate ions in the pregnant solution is revealed as a key factor in controlling the nature of the precipitating phase. Synthetic aluminate solutions of varying sodium carbonate concentrations, ranging from 20 to 160 g/L, were carbonated, and the resulting precipitating phases were characterized by X-ray diffraction analysis. Based on the results of the previous carbonation tests, a series of experiments were performed in which the duration of carbonation and the aging period of the precipitates varied. For this work, a synthetic aluminate solution containing 20 g/L free Na2CO3 was used. The precipitates were characterized with X-ray diffraction analysis and Fourier-transform infrared spectroscopy.

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Carbonation of Sodium Aluminate/Sodium Carbonate Solutions for Precipitation of Alumina Hydrates—Avoiding Dawsonite Formation

Phase Transformations during Aging of Aluminum Hydroxide Precipitated by Hydrogen Peroxide

The effect of pH and seeding were studied on phase, particle size, morphology, purity and conversion of aluminum hydroxide produced by carbonation of solution of sintered nepheline syenite alkaline...

Peyman Hassanpour

Papers

Aluminum hydroxide crystallization from aluminate solution using carbon dioxide gas: effect of pH and seeding