Efficient Nickel and Cobalt Recovery by Metal-Organic Framework-Based Mixed Matrix Membranes (MMM-MOFs)

Area of Science:

• Materials Science
• Environmental Chemistry
• Chemical Engineering

Background:

• The green energy transition necessitates a robust supply of raw materials like cobalt and nickel for electric vehicle batteries.
• Current mining practices and ore localization create supply chain vulnerabilities for these critical metals, hindering renewable energy progress.
• Sustainable recycling methods are crucial to mitigate shortages and environmental impact associated with cobalt and nickel extraction.

Purpose of the Study:

• To investigate the efficacy of mixed matrix membranes (MMMs) incorporating various metal-organic frameworks (MOFs) for cobalt and nickel recovery.
• To evaluate the performance of MOF@PES MMMs in removing Co(II) and Ni(II) from aqueous solutions containing interfering ions.
• To identify the most effective MOF@PES MMM for sustainable metal recycling from wastewater and spent lithium-ion batteries.

Main Methods:

• Fabrication of four distinct MOF@PES MMMs using MIL-53(Al), MIL-53(Fe), MIL-101(Fe), and SrCuSer MOFs embedded in a polyether sulfone matrix.
• Testing the adsorption performance and removal efficiency of the fabricated MMMs for Co(II) and Ni(II) from aqueous solutions.
• Comparative analysis of MOF@PES MMMs against neat PES membranes and assessment of selectivity for cobalt over nickel.

Main Results:

• Neat PES membranes showed limited removal efficiency (10.2% Ni(II), 9.5% Co(II)).
• MOF@PES MMMs significantly enhanced metal ion adsorption, with MIL-53(Al)@PES achieving up to 95% removal for both Ni(II) and Co(II).
• SrCuSer@PES demonstrated high selectivity for Co(II) (63.7% removal) over Ni(II) (15.1% removal).

Conclusions:

• MOF@PES MMMs are highly effective adsorbents for recovering cobalt and nickel from aqueous solutions.
• MIL-53(Al)@PES and SrCuSer@PES show promising performance for selective metal recovery, contributing to sustainable recycling efforts.
• The developed MOF@PES MMMs offer a versatile, robust, and cost-effective solution for critical metal extraction, supporting the green energy transition.