The engineers turning waste salt into the energy transition's missing link

The article highlights how two engineers, Bilen Aküzüm and Lukas Hackl, co-founders of Aepnus Technology, identified a significant but overlooked bottleneck in the battery supply chain: the chemical waste generated during mineral processing. Specifically, lithium extraction and battery recycling plants produce large amounts of sodium sulfate waste while simultaneously importing costly reagents like caustic soda (sodium hydroxide) and sulfuric acid. This linear chemical use results in high operating expenses—up to 30-40% of costs—and environmental burdens due to waste disposal. Motivated by this paradox, the engineers developed an innovative electrolyzer system that converts waste sodium sulfate back into valuable reagents, effectively closing the loop on industrial chemistry. After five years of research, pilot projects, and material science advances, Aepnus Technology’s electrolyzer has demonstrated reliable, energy-efficient conversion of sodium sulfate into high-purity caustic soda and sulfuric acid without relying on rare catalysts. This breakthrough addresses a critical but under