| Abstract Scope |
Membrane-divided electrolysis enables critical mineral recovery with in-situ reagent regeneration, but commercial membrane cost and fouling have blocked mining-scale adoption. We report a homogeneous ion exchange membrane made from pulverized commercial resin dispersed in a PVC or CPVC matrix, cast from solvent at materials cost below one dollar per square foot, roughly two orders of magnitude below commercial alternatives, with the recipe published under CERN-OHL-S v2. The membrane has operated for a year in acidic, high-ORP leach solutions. Built around it, the SEM TECH platform performs continuous closed-loop leaching and recovery: chloride oxidizers and hydrochloric acid are generated in situ from brine and electricity, and dissolved metals are recovered as mixed concentrates. Campaigns on raw ore, high-sulfide ore, tailings, and mine waste liquids produced concentrated mixed-metal powders with confirmed rhodium recovery. Preliminary estimates span 300 to 2200 kWh per ton. We present membrane fabrication, cell architecture, performance, and scale-up path. |