Summary
– Beijing University of Chemical Technology team used formic acid-hydrogen peroxide for selective leaching of lithium ions from batteries
– Achieved optimal leaching conditions through single-factor optimization
– Verified optimal conditions through response surface experiments
– Formic acid and hydrogen peroxide used for recovery have advantages of simplicity and high purity
– Recovery technology offers high lithium concentration with minimal iron ions
Article
A team from the Beijing University of Chemical Technology has developed a process for selectively leaching lithium ions from spent lithium iron phosphate batteries using a formic acid-hydrogen peroxide system. The team optimized the leaching conditions through single-factor optimization, achieving a lithium leaching extent of 99.9% with minimal iron leaching. The optimal conditions included a formic acid concentration of 0.8 mol/L, solid-liquid ratio of 50 g/L, initial hydrogen peroxide volume fraction of 8%, temperature of 60°C, and a reaction time of 1 hour.
The team further validated the optimal leaching conditions through multi-factor response surface experiments, obtaining results consistent with the single-factor optimization. They were able to achieve a primary precipitation extent of 85.05% and a lithium product purity of 99.9% by using sodium carbonate precipitation to recover lithium ions from the leach filtrate. The authors highlighted the advantages of using formic acid and hydrogen peroxide in their process, emphasizing the simplicity, efficiency, and environmental friendliness of the technology.
Formic acid was chosen as the leaching agent due to its characteristics of being less acidic, green, easily decomposed, and less polluting compared to inorganic acids. Hydrogen peroxide served as the oxidizing agent in the process. The authors emphasized the benefits of their proposed recovery technology, noting the high lithium concentration in the leaching solution with minimal iron ion content and the high purity of lithium carbonate obtained. Overall, the process offers a simple, short, and effective method for recovering lithium ions from spent lithium iron phosphate batteries.
The research conducted by the team from the Beijing University of Chemical Technology was published in the Journal of Power Sources, highlighting the significance of their findings in the field of battery recycling and lithium ion recovery. By utilizing formic acid and hydrogen peroxide in their selective leaching process, the team was able to achieve high lithium leaching efficiency while minimizing iron leaching. The use of sodium carbonate precipitation further enhanced the recovery of lithium ions, resulting in a purified lithium carbonate product with high purity and primary precipitation extent.
The authors’ work demonstrates the feasibility of using a formic acid-hydrogen peroxide system for selective leaching of lithium ions from spent batteries, offering a promising avenue for sustainable battery recycling practices. The technology’s simplicity, efficiency, and environmental advantages make it a promising solution for recovering valuable resources from electronic waste. The results of this study provide valuable insights for future research in the field of lithium ion recovery and contribute to the development of more sustainable and efficient recycling processes for battery materials.
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