Nanoscale electrodes separate salt from seawater. It uses special electrodes:
"It first draws ions from seawater into a pair of electrodes. As the researchers pass current through the electrodes, electrochemical reactions drive chloride ions into a silver electrode and sodium ions to an electrode made from manganese oxide nanorods. Next, the researchers remove the desalinated water and release the trapped ions into a separate stream of waste seawater by reversing the direction of the electrical current."
And at this point the salt in the water is only reduced by about 50%.
posted by aleph
on Feb 11, 2012 -
Is blood plasma salinity the same as seawater? No, but that proves evolution. "The answer is most definitely NOT that oceans were 1/3 as salty back then. It most definitely IS that the earliest vertebrates did evolve in salt water and then moved into fresh water....They have devised an extremely clever trick in kidney structure to allow salt transport pumps which really take salt back INTO the body from the urine but still manage to use them to produce urine much more concentrated that their body fluids and so excrete salt FROM the body."
posted by Brian B.
on Feb 10, 2007 -