IBM has unveiled new membrane technology which purifies water while using less energy than other methods.
The collaborative effort between IBM, Tokyo-based Central Glass and the King Abdul Aziz City for Science and Technology (KACST) stands to alleviate the growing shortage of drinkable water worldwide.
The new membrane filters out salts as well as potentially harmful toxins in water such as arsenic while using less energy.
According to the World Health Organization, arsenic-contaminated water has been a major health concern worldwide since the 1990s.
Membrane filtration is currently one of the most energy efficient techniques for removing salt and improving water quality. However, conventional membranes are easily damaged by chlorine, a common chemical used to prevent bacterial growth in water.
The new membrane material is resistant to chlorine damage, and displays high performance separation behaviour in mildly basic conditions, making it suitable for arsenic removal in addition to water desalination.
The membrane contains ionizable hydrophobes, upon encountering mildly basic conditions, become substantially hydrophilic. The membrane transforms from a low water transporting filter to a high water transporting state in a basic environment.
The high pH also causes arsenic to become ionic resulting in a relatively easy separation by desalination membranes. Because of these conditions and reactions, when contaminated water is forced through the membrane, the arsenic is filtered out.