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Graphene Membranes Superpermeable to Water
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."
It's not mentioned in the opener, but the article says it lets water "evaporate" through it.
So it's not like you can just pour water on it, and let it drip through.
I wonder if this just means steam can pass through it, or if it has to evaporate on the graphene for it to get through?
If it was the former, then why are they wording it so complicated?
The material they used was NOT graphene. It was graphene oxide.
...you don't need a pressure source like you do for reverse osmosis?
Even if it does not, I would think it would be much more resilient toward chlorine and iron. Perhaps it won't need as much pretreatment done to the water as a conventional film membrane requires. Currently most decent RO systems have a 10 micron sediment filter, followed by 5 and 1 micron carbon filters. If you have high iron content in the feed water, then you need a softener or some other way to reduce it prior to the sediment filter too. Since the three RO pre-filters typically need to be replaced every 6-12 months, they are the most frequent replacement item. A typical RO membrane last 2-5 years. Perhaps this would be lengthened too.
What you need is to make sure you obtain the electrolytes and minerals from some other source to avoid insufficiency. Other than that, pure water is safe to drink.
Informative? How about flamebait. This is simply not true. Absolutely insanely pure water is just water. Your body doesn't react to a 0.0001% difference in dissolved solids. After a microsecond in your mouth the water is far from pure.
Gaseous helium difuses through pretty much everything. These graphene membranes should have truly amazing properties.
Armies of physicists will work years to explain such remarkable phenomenons. Neutrinos light than faster like just.