Daniel Rau

Daniel Rau, who earned a bachelor’s in chemical engineering from Vanderbilt University, founded Kunin in January 2025 after attempting to commercialize a lithium mining extraction technology from Vanderbilt University. Daniel was selected as a 50 Years Venture Fellow and Harpoon Ventures Black Flag Fellow, lectured on the lithium industry at Tulane University, and appeared on the Money of Mine podcast for lithium market analysis. In May 2025, Daniel raised a preseed round from Harpoon Ventures, SpaceX engineers, and mining angel investors.

This past summer, Daniel relocated his company to Chattanooga, Tennessee, to be close to ORNL, Tennessee mining operations, and a local manufacturing partner. Daniel’s experience spans hydrogen fuel cells, biofuels, synthetic aviation fuels, and battery recycling in fundamental research, early-stage investing, and process engineering across US national labs, oil and gas companies, and Arcadium Lithium.

Key Innovation

Kunin is developing a nanofiber ion exchange technology platform for scavenging and recovering critical minerals. Current ion exchange technology uses microporous ion exchange resin beads that contain a crosslinked polymer backbone for stability and specially engineered functional chemistry for selective metal ion extraction. In mining, ion exchange involves processing aqueous solutions borne from the mineral processing and leaching of mined ores by passing the solution through a large column containing a packed bed of beads. Fluid penetrates resin beads, in which dissolved metal ions selectively bind to functional chemical groups on the solid surface, such as a chemical or metal sponge. The ion exchange resin bead system has enabled profitable recovery of metals, such as copper, cobalt, nickel, gallium, and uranium, but increasingly has been weaponized by Chinese companies that possess a competitive edge through vertical integration from resin manufacturing, column design, and turnkey engineering services.

Today, many of the critical minerals that the United States relies on are recovered as secondary, tertiary, or quaternary by-products from operating mines using ion exchange technology. To restore US critical mineral independence, Kunin is developing a polymer nanofiber membrane version of the ion exchange resin bead to improve metal ion separation kinetics—it has the same polymer chemistry and same functional chemistry but a different form factor that possesses 100 to 1,000 times higher specific surface areas.

Through a partnership with Chattanooga nanofiber manufacturing partners, Kunin has developed a proprietary nanofiber module system that outperforms bead columns by 15 times on throughput. Kunin plans to vertically integrate to nanofiber manufacturing, module manufacturing, process controls development, and turnkey engineering solutions to unlock critical mineral production at domestic mining assets.

ORNL Principal Investigator

• Tomonori Saito - Synthetic Polymer Chemist, Soft Materials and Membranes, Chemical Sciences Division, Physical Sciences Directorate