With further development, these membranes have significant potential to perform the dual functions of removing salts from seawater and separating metal ions in a highly efficient and cost effective manner, offering a revolutionary new technological approach for the water and mining industries.

Currently, reverse osmosis membranes are responsible for more than half of the world’s desalination capacity, and the last stage of most water treatment processes, yet these membranes have room for improvement by a factor of 2 to 3 in energy consumption. They do not operate on the principles of dehydration of ions, or selective ion transport in biological channels, the subject of the 2003 Nobel Prize in Chemistry awarded to Roderick MacKinnon and Peter Agre, and therefore have significant limitations.

In the mining industry, membrane processes are being developed to reduce water pollution, as well as for recovering valuable metals. For example, lithium-ion batteries are now the most popular power source for mobile electronic devices, however at current rates of consumption, there is rising demand likely to require lithium production from non-traditional sources, such as recovery from salt water and waste process streams. If economically and technologically feasible, direct extraction and purification of lithium from such a complex liquid system would have profound economic impacts.

Source: Researchers discover efficient and sustainable way to filter salt and metal ions from water