Three-quarters of a billion people around the world don't have access to clean water, a problem that is compounded by the fact that 90 percent of wastewater in developing countries flows untreated back into rivers, lakes and coastal areas. But thanks to a new device developed at MIT, removing contaminants from water has become more efficient than ever and marks an important step toward reducing water-related health problems around the world.
For the most part, polluted or brackish water is treated in one of three ways: membrane filtration, electrodialysis, or capacitive deionization. Membrane filtration uses ultrafine porous materials to strain pollutants and microorganisms from water, whereas electrodialysis and capacitive deionization remove salt from brackish water using an electric current. While these approaches work well enough, membrane filtration is expensive and not so effective when pollutants are in water in low concentrations, and electrical methods tend to require large amounts of energy.The new device developed by MIT, however, takes advantage of electrochemical processes to remove even trace amounts of contaminants from water and its energy requirement is low enough that it could easily be solar powered. Moreover, unlike other water purification systems, this device can target the removal of specific pollutants, rather than just functioning like a catchall net.Continue reading on Motherboard.