I-Corps: Translation Potential of Bipolar Membrane Applications in Extractive Metallurgy

This I-Corps project is based on the development of a system that converts salty water into concentrated acid and base using only electricity. Acid is widely used in metal refining processes from primary extraction to product finishing across metals including nickel, lithium, rare earths, and steel. However, current acid production and recycling methods are often associated with the generation of hazardous gases that must be managed.

The transportation of acids and precursor chemicals adds further logistical complexity and costs to metals processing plants, especially where primary extraction occurs at remote mining sites. Spent acid is often wholly or partially neutralized on site to form salts of calcium, magnesium, sodium, or iron, which can pose environmental risks and space constraints to mine or refinery sites and surrounding ecosystems.

Acid procurement and waste management can account for 30% to 80% of operating expenditures in metals leaching processes. This technology may offer a safer, cleaner, and more energy-efficient alternative for metal extraction with no direct emissions or hazardous byproducts. In addition, this technology may enable sustainable domestic supply chains for critical materials.

This I-Corps project utilizes experiential learning coupled with first-hand investigation of the industry ecosystem to assess the translation potential of a bipolar membrane electrodialysis platform for acid and base production. The adoption of bipolar membrane electrodialysis in metallurgy has been limited due to the low concentrations of acid electrodialysis can produce with current technology.

Metals leaching typically requires more concentrated acids and bases than in common applications of electrodialysis such as in the beverage or desalination industries. This technology allows for the doubling of acid concentrations versus traditional electrodialysis by optimizing membrane compositions, reactor component sizing, and operational parameters.

Unlike conventional acid generation technologies, this approach avoids combustion, phase changes, or hazardous byproducts. The research builds on recent advances in membrane materials and stack design to improve efficiency and durability, allowing for high-throughput operation with minimal downtime. This technology may enable production of concentrated acid and thus, has important applications in metallurgy, where concentrated acids are widely used to extract metals from ores.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.