The new technique of Seawater Desalination

By creating a small electric field to remove salt from seawater, a chemist team at the University of Texas at Austin, USA, and the University of Marburg in Germany discovered a new method for seawater desalination which only requires less energy and much simpler than the usual techniques. So little energy needed within this new method so that it can operate only with regular batteries.

The process is negates the problems that facing the current desalination methods because it does not require salt filter membrane. The chemist was able to separate the salt from seawater at the micro scale to produce fresh water more faster.

A prototype 'water chip' developed by researchers at The University of Texas at Austin and University of Marburg in Germany, in collaboration with a startup company. (Picture from: http://cleantechnica.com/)

The technique which is called seawater desalination by electrochemical intermediary is described in the Angewandte Chemie journal. The researcher team led by Richard Crooks of the University of Texas and Ulrich Tallarek from the University of Marburg. They were filed for a patent on a method that is now commercially developed by startup company Okeanos Technologies.

"The availability of water for drinking and irrigation is one of the most basic needs to maintain and improve human health," said Crooks. "Desalination is one way to meet this need, but most of the existing methods are too expensive and the membrane is easily contaminated."

The membrane-free method developed by Crooks and his team is still need to be improved and scaled up, "But, if we succeed, someday we can provide fresh water in a large scale by using a simple system, perhaps even portable."

"People are dying because of a lack of freshwater," said Tony Frudakis, founder and CEO of Okeanos Technologies. "And they’ll continue to do so until there is some kind of breakthrough, and that is what we are hoping our technology will represent."

Right now the water chip's microchannels, produce about 40 nanoliters of desalted water per minute. But the authors are confident the process can scale up to make it practical to produce liters of water per day. "Okeanos has even contemplated building a small system that would look like a Coke machine and would operate in a standalone fashion to produce enough water for a small village," Frudakis said.

To separate the salt from seawater, researchers distribute small electric voltage (3.0 volts) on a plastic chip containing seawater. The chip containing micro channels with two branches. At the junction canal, electrodes are implanted underneath will neutralize the chloride ions in seawater to create an "ion depletion zone" which creates a local electric field. Changes in the electric field is sufficient to move the salt to the other branches, so that the water that has been through a desalination process flow to another branch. *** [EKA | FROM VARIOUS SOURCES | SCIENCEDAILY | TJANDRA DEWI | KORAN TEMPO 4276]
Note: This blog can be accessed via your smart phone.