Desalination: IBM unveils new membane technology

Scientists at IBM Research, together with collaborators from Tokyo-based Central Glass, the King Abdul Aziz City for Science and Technology (KACST) and the University of Texas, Austin have created a new membrane that filters out salts as well as potentially harmful toxins in water such as arsenic while using less energy than other forms of water purification.

[...] Membrane filtration is currently one of the most energy efficient techniques for removing salt and improving water quality. But, conventional membranes used today are easily damaged by chlorine, which is commonly added to water to prevent bacterial growth that can cause health problems. Now, the collaborative research team has designed a new concept in membrane materials that combines resistance to chlorine damage and high performance separation behavior in mildly basic conditions, making it suitable for arsenic removal in addition to water desalination.

[...] Because of its unique chemistry, the membrane contains ionizable hydrophobes that undergo a dramatic change when they encounter mildly basic conditions – they become substantially hydrophilic. In short, the membrane, which is made with fluorine materials, transforms from a low water transporting filter to a high water transporting state in a basic environment – what the researchers call a “water superhighway.” Fortuitously, 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.

See also: IBM Unveils Smart Technologies, Services to Help Combat Mounting Global Water Issues, IBM, 16 Mar 2009

Web site: IBM Advanced Water Management

Source: IBM, 16 Mar 2009