Data from the World Health Organization (WHO) indicate that around 785 million people around the world do not have a clean source of drinking water. Despite the large amount of water on Earth, only 2.5% is fresh, the rest is water that cannot be used for human consumption.
One of the ways to provide clean drinking water to the entire world population is through a process of desalination of ocean water. Faced with this situation, the Korea Institute of Civil Engineering and Construction Technology (KICT) developed an electrospun nanofiber membrane to convert seawater into drinking water.
To carry out this process, the KICT research team developed coaxial electrospun nanofiber membranes manufactured by an alternative nanotechnology technique called electrospinning. That is, the material has the ability to prevent wetting problems and improve the long-term stability of the water desalination process.
Yunchul Woo, KICT professor and project leader pointed out that common membranes often have moisture seepage problems, therefore it is difficult to carry out a stable desalination process. “If a membrane is completely wetted, its performance drops dramatically and the process of converting salt water to fresh water is almost impossible,” he said.
In addition, the scientist Woo explained that the coaxial electrospinning technique is one of the most favorable and simple options for manufacturing membranes with three-dimensional hierarchical structures. To produce a composite membrane, you only need to obtain silicon airgel and expose it to a much lower thermal conductivity compared to any polymer. Thus, the material has a better conductivity of the water vapor flow during the water desalination process without losing heat.
The most outstanding result by the researchers was that most conventional nanofibers only have a life time of 50 hours, after which they decrease their effectiveness. In contrast, the desalination process with the coaxial electrospun nanofiber membranes was effective for one month, that is, 31 days. Also, he rejected 99 percent of the salt resulting in the desalination membrane working long term.
It should be noted, this new desalination technology shows that it has enormous potential to solve the world’s fresh water shortage. A nanofiber membrane could be the solution to desalinate the water of the seas and with a great opportunity to be a commercially feasible product on a large scale.