Table of Contents
- Process Overview
- Liquid-Liquid-Equilibrium (LLE) Contactors
- Cobalt Recovery Step
- Yield Calculation with the Calculator Block
- Video Demo
- Additional Solvent Extraction Resources
Objective
This article demonstrates a model for cobalt recovery using a solvent extraction technique in OLI Flowsheet: ESP, leveraging OLI’s comprehensive species database. The database includes key extractants and solvents relevant to the critical materials sector. This demonstration highlights how to model a prototypical hydrometallurgical process in OLI Flowsheet: ESP with high accuracy.
Disclaimer: The user interface, calculations, and results displayed in this article are from OLI Flowsheet: ESP Version 12.0. Other software versions may appear different due to continual developments to the software.
Process Overview
This model stems from a larger battery recycling simulation focusing on cobalt and lithium extraction from lithium cobalt oxide (LCO) cathodes. The hydrometallurgical section incorporates the feed composition and cobalt extraction techniques outlined in (1). The process involves pH neutralization and precipitation to remove impurities, two-stage countercurrent solvent extraction section, and a one-stage strip section to extract cobalt from the organic phase.
In this example, the following inlet streams mix:
- Cobalt-containing stream
- Hydroxide and carbonate stream to meet the Feedback Controller’s target pH of 6.2
- An organic solvent (kerosene) with Cyanex272 as the extractant
Liquid-Liquid-Equilibrium (LLE) Contactors
- Cyanex272 is introduced to the 2nd Stage LLE contactor, recycling into the 1st Stage LLE, while the Co(+2)-containing feed is introduced to the 1st Stage LLE.
- By incorporating two separators, we create two stages for the extractant to react with Co(+2), enhancing its partitioning into the organic phase
Cobalt Recovery Step
- A solution (2M H2SO4) is mixed with the cobalt-rich organic phase to partition the majority of Co(+2) into the aqueous phase (“Recovered Cobalt”)
Yield Calculation with the Calculator Block
- A Calculator Block is added to determine and display cobalt recovery as a mole percentage. For more information on how to build a Calculator Block, please refer to our related Support Center article.
- Two local properties:
- Co_In: Co(+2) input
- Co_Recovered: Co(+2) in the outlet aqueous stream
- Final Expression: Yield = (Co_Recovered / Co_In) x 100
Additional Solvent Extraction Resources
- OLI Systems Introduces Novel Solvent Extraction Database for Enhanced Battery Recycling Process Simulation
- OLI's V12 Database Supports Simulation of Solvent Extraction for Recovery of Critical Materials from Spent Lithium-Ion Batteries (Figure 1 indicates the solvents currently available in OLI's database that apply to cobalt, nickel, or lithium)
- Enhancing Solvent Extraction Efficiency in Nickel, Cobalt, and Rare Earth Element Production: Modeling Mass, Chemistry and Heat Balance with OLI Software
- Maximizing Nickel and Cobalt Recovery from Battery Waste Using Solvent Extraction
Conclusion
This example highlights OLI’s strength in key processes of the critical materials industry, such as battery recycling, direct lithium extraction, and more. For any questions or assistance on troubleshooting your model, please submit a ticket at support.olisystems.com.
References
- J. Kang, G. Senanayake, J. Sohn, S. M. Shin, Recovery of cobalt sulfate from spent lithium-ion batteries by reductive leaching and solvent extraction with Cyanex 272. Hydrometallurgy, 2010. 100(3-4): p. 168-171.