08 April 2024 | Shuqi Xu, Alice J. Hutchinson, Mahdiar Taheri, Ben Corry, Juan F. Torres
Thermodiffusive desalination (TDD) is a novel method for water desalination that operates entirely in the liquid phase, avoiding the issues of scaling, fouling, and material degradation associated with conventional thermal desalination methods. TDD leverages thermodiffusion, the migration of species under a temperature gradient, driven by thermal energy available in the environment. Experimental results show that TDD can achieve a 450 ppm concentration drop in a single pass through a NaCl/H₂O solution, which can be further increased through recirculation. Molecular dynamics and experiments demonstrate that TDD is more effective in multi-component seawater compared to binary NaCl/H₂O solutions. Numerical simulations indicate that a scalable cascaded channel structure can achieve a concentration drop of 25,000 ppm with a recovery rate of 10%, making it suitable for high-throughput desalination. TDD has the potential to be particularly useful in areas with abundant thermal energy but limited electrical power resources, contributing to the alleviation of global freshwater scarcity. The method is also promising as a pre-treatment for existing desalination technologies like reverse osmosis (RO) and electrodialysis (ED), and as a standalone technology for low-salinity water production.Thermodiffusive desalination (TDD) is a novel method for water desalination that operates entirely in the liquid phase, avoiding the issues of scaling, fouling, and material degradation associated with conventional thermal desalination methods. TDD leverages thermodiffusion, the migration of species under a temperature gradient, driven by thermal energy available in the environment. Experimental results show that TDD can achieve a 450 ppm concentration drop in a single pass through a NaCl/H₂O solution, which can be further increased through recirculation. Molecular dynamics and experiments demonstrate that TDD is more effective in multi-component seawater compared to binary NaCl/H₂O solutions. Numerical simulations indicate that a scalable cascaded channel structure can achieve a concentration drop of 25,000 ppm with a recovery rate of 10%, making it suitable for high-throughput desalination. TDD has the potential to be particularly useful in areas with abundant thermal energy but limited electrical power resources, contributing to the alleviation of global freshwater scarcity. The method is also promising as a pre-treatment for existing desalination technologies like reverse osmosis (RO) and electrodialysis (ED), and as a standalone technology for low-salinity water production.