Mohsenzadeh, MiladXu, ShuqiShamet, OsmanTorres, Juan F.2026-07-032026-07-03ORCID:/0000-0002-3054-8638/work/219172790https://hdl.handle.net/1885/733812653Industrial processes generate over 200 million metric tonnes of brine each day, posing serious environmental challenges due to its high salinity, toxicity, and energy-intensive treatment requirements. Conventional treatment methods, such as reverse osmosis and evaporation ponds, face limitations in scalability, energy efficiency, and environmental impact. Here, we demonstrate that multichannel thermodiffusion—an emerging membrane- and evaporation-free method driven by temperature gradients—can effectively concentrate brines beyond 70 ppt (parts per thousand), approaching saturation. Using a liquid Burgers cascade, we show that thermodiffusive separation becomes more efficient at higher feed concentrations and can be scaled using low-cost, rapidly fabricated 3D-printed components. Furthermore, we demonstrate the versatility of the technique by applying it to an industrially relevant feed including LiI, K2SO4, and NaOH. Our results indicate that thermodiffusion, previously regarded as ‘too weak for practical use’, offers a sustainable, scalable, and energy-efficient pathway toward minimal liquid discharge and potentially resource recovery from concentrates.This research was funded by the Australian Department of Foreign Affairs and Trade (Grant type: SciTech4Climate) and Wacomet Water Co.enPublisher Copyright: © The Author(s) 2025.202510.1038/s41545-025-00526-7105022289188