Graphene Membranes Superpermeable to Water 292
Dr Max writes "Not only is graphene the strongest, thinnest and best conducting material known to man, it is now shown to have superpermeability with respect to water as well. This allows a membrane made with graphene to pass water right through it (PDF), while another atom or molecule (even helium) gets blocked. 'The properties are so unusual that it is hard to imagine that they cannot find some use in the design of filtration, separation or barrier membranes and for selective removal of water,' said one of the researchers."
Does this mean... (Score:2, Insightful)
...you don't need a pressure source like you do for reverse osmosis?
Re:Does this mean... (Score:5, Insightful)
Used to collect gifts from Shai-Hulud (Score:5, Insightful)
Now we know what the water receptacles in Dune were made of.
Fresh water? (Score:5, Insightful)
If it blocks Helium (Score:5, Insightful)
Helium molecules are very small. It is difficult to contain Helium gas in cylinders.
There are even far more important applications for the global economy. It may finally be possible to make Helium balloons that don't leak the tiny molecules so quickly.
Re:Fresh water? (Score:3, Insightful)
The atoms might be at least 4.5 billion years old, but not *every* molecule of water is of that age.
Re:Fresh water? (Score:4, Insightful)
Spend a little time thinking about it, and you will realize that distilled water urban legend is silly. In your mouth, it is mixed with saliva and mucous and whatever else is stuck to your teeth, gums, and tongue. The instant it hits your stomach, it is mixed with stomach acids and whatever you ate recently. I.e. it is no longer pure distilled water. From there, the molecules wander through your body like any other water molecule. Distilling water does not give its component molecules magic properties.
Re:Does this mean... (Score:5, Insightful)
Yes, but here they're showing that the membrane allows WATER through but will stop HELIUM. If I'm not mistaken, helium molecules are smallerthan water molecules. That's the freakish quality.
Re:Fresh water? (Score:5, Insightful)
Water is formed from hydrogen and oxygen. It is not inert, it decomposes and reforms constantly. So, no, water molecules are not at least 4.5 billion years old.
The hydrogen and oxygen atoms that make up water, or at least most of them, may well be much older than that. Particularly the hydrogen, which may be over 13 billion years old.
Re:Does this mean... (Score:3, Insightful)
You're using energy to get that water higher than it's final location, just like a pump.
Re:Does this mean... (Score:5, Insightful)
Oxygen being in the center of a water molecule pretty much makes it larger than helium in ALL directions.