A partnership between The University of Manchester and Khalifa University of Science and Technology in Abu Dhabi has yielded graphene-based membranes aimed at to taking salts out of water.
The most popular method for water desalination currently is a process called reverse osmosis, which requires large quantities of water to be forced through a membrane to remove the salts in the water. This method is particularly useful when there is a high salt content, however more efficient methods are required for bodies of water that have a lower salt content, known as brackish water. The team of researchers has developed new ion-selective membranes incorporating graphene oxide, for use in electromembrane desalination processes such as electrodialysis and membrane capacitive deionization.
Using a series of membranes, the ions in the saltwater can be driven out by an electric field, allowing clean water to be achieved.
“This collaboration is enabling us to develop both membranes that like positively charged ions and membranes that like negatively charged ions, and together they offer exciting possibilities for helping achieve the global goal of clean water for all", said Professor Peter Budd, Professor of Polymer Chemistry
Professor Linda Zou from Khalifa University of Science and Technology said: “We prepared the electrostatically-coupled graphene oxide nanocomposite cation exchange membrane, where all the ion exchange groups are provided by ionic conducting nanomaterials. The collaboration between two teams provided great support to each other in complementary aspects of the research, and led to positive research outcomes, and more to come”.
Dr Gyorgy Szekely, from King Abdullah University of Science and Technology said: “The application of graphene-based nanocomposites allowed us to control and improve the properties of ion-exchange membranes. The novel separation materials developed for desalination in this collaboration have the potential to increase the efficiency and therefore to cut the costs of the electromembrane processes producing clean water. Our previous joint publication under the flagship of the Graphene Engineering Innovation Center was featured on the front cover of the Journal of Materials Chemistry A, which demonstrates the broad scientific interest in this topic.”