Process Parameters and Optimization Conditions for Recovering Cobalt from Spent Lithium Cobalt Oxide Batteries Using the P507 Extractant

With P507 extractant Key Process Parameters for Cobalt Recovery from Spent Lithium Cobalt Oxide Batteries

(1) with P507 extractant Aviation kerosene is used as a diluent to extract aluminum from the leachate of spent lithium-ion battery cathodes, achieving highly favorable results in the separation of cobalt and aluminum. Under the extraction conditions, the aluminum concentration in the leachate is reduced by a factor of 0.6 × 10⁻⁷ relative to the initial solution, with an extraction efficiency of 99.6%. The purity of cobalt in the solution reaches 99.99%.

(2) The optimized conditions for the extraction and separation of cobalt and aluminum are as follows: 30% P507–kerosene, saponification rate of 40%, pH = 1.7, and a volume ratio of organic to aqueous phase of 1:1.

(3) P507 was used to separate cobalt and aluminum from the leaching solution of lithium cobalt oxide, with extractant concentrations of 50% and 30%, respectively. The results indicate that P507 at both 50% and 30% concentrations exhibits comparable extraction performance in the separation of cobalt and aluminum.

When extracting with a higher concentration of P507, the saponification rate is lower, allowing for better cobalt–aluminum separation; however, this approach entails higher costs.

When extracting with a lower-concentration P507 extractant, the extraction capacity can be enhanced by increasing the saponification rate, thereby achieving improved cobalt–aluminum separation. However, a significant drawback is the substantial loss of cobalt in the raffinate.

In industrial applications, P507 extraction agent The concentration should be determined based on the actual conditions, such as the cobalt and aluminum concentrations in the leachate.

The primary functions of extractants include: separating target metal ions from impurity ions, concentrating the target metal ions, purifying metal ion solutions, and altering the nature of anions. P507 and P204 extractants are widely used in hydrometallurgy, rare‑earth processing, and non‑metallic solvent extraction, particularly in the smelting of ferrous metals. The diluents employed in the extraction process are Maoming Zhengmao Petrochemical’s No. 260 solvent oil and sulfonated kerosene. These systems offer high extraction efficiency with low losses. In fact, P204 and P507 exhibit only moderate toxicity; however, poor sealing of extraction equipment or inadequate ventilation can result in unpleasant odors. Moreover, these extractants are predominantly utilized in the hydrometallurgical processing of non‑ferrous metals, including copper, zinc, cobalt, nickel, cadmium, gold and silver, platinum‑group metals, and rare earth elements.

P507 extraction agent Precautions for Use

P507 extraction agent It should exhibit good selectivity. During the extraction process, the extractant must effectively dissolve the solute of interest while remaining insoluble or only sparingly soluble in other solution components such as the diluent. In selecting the solvent system, the extractant should be chosen with a well-defined target. The extractant should also possess favorable physical properties, as these directly influence the efficiency and operation of the extraction process. Furthermore, it should demonstrate excellent chemical stability; the integrity of its chemical stability is critical to the safety of the extraction procedure. Accordingly, preference should be given to extractants that are less corrosive, undergo minimal polymerization or decomposition, and exhibit strong resistance to oxidation and thermal degradation.