Scientists at the University of California at Los Angeles have invented a new membrane which can filter salt and impurities out of seawater more efficiently and cheaper than current systems.
The membrane, developed by Eric Hoek, consists of a matrix of porous polymer sheets embedded with specially designed nanoparticles. The nanoparticles attract water molecules and repel other particles. In reverse osmosis, seawater passes through porous membranes. The pores allow water to pass, but are too small for salt and other particles, thereby purifying the water.
The nanoparticles, because they attract water and repel other substances through their inherent chemical properties, cut in half the amount of energy required to pump the water through the membrane. That in turn could cut the cost of turning seawater into drinking water by around 25 percent.