Graphene sieve capable of desalination

Is this it, a hope for access to H20 for all, can it be made cost effective, I belive any cost shoould be effective when balanced against human life (that can be another thread though)

I have read of others but this one has WAY more promise, why you say well firstly

Reporting their results in the journal Nature Nanotechnology, scientists from the University of Manchester

Makes Alan Turing Way even more inspiring (alongside the GREATEST football team )

It surely must be better than this scenario posed by the UN

By 2025 the UN expects that 14% of the world's population will encounter water scarcity

8 years before upto 1 billion people on a planet which is almost 2/3s water, maybe stop making big guns and start using our brains more

"The ultimate goal is to create a filtration device that will produce potable water from seawater or wastewater with minimal energy input."

The water on this planet has always been here, going thru the water cycle for millennia, about time we harnessed more of it.

www.bbc.co.uk...

www.nature.com... ml

This special material is a film of a special structure of carbon, a honeycomb lattice called graphene.

"Graphene is pure carbon that is made in a hot oven on top of a copper sheet in a vacuum," John Stetson, the chief technologist at Lockheed for this initiative explained to Business Insider. "Methane gas is put into the vacuum and the methane changes into a single film of carbon atoms all linked together tightly like chickenwire (at the atomic level) 1,000 times stronger than steel and tolerant of temperature, pressure and pH."

The sheet is dotted with holes that are one nanometer or less. These holes between carbon atoms trap the salt and other impurities.

Business Insider, March 22, 2013 – Lockheed Martin Says This Desalination Technology Is An Industry Game-Changer.

OP (EternalSolace)’s link (where the Lockheed article came from) is in this thread: Earth's Fresh water scarcity may be solved.

Nice! I did a search on this topic since it has been posted several times over the years. But I did not know the following: Lockheed figured out how to make the graphene version in 2013!!

OP’s announcement here is about graphene oxide [GO] being bound in epoxy to prevent the graphene oxide pores from expanding (because the graphene oxide will do that). The graphene version is much more efficient. You add pressure from that side and the water “lines up” to pass through the pores without the unwanted impurities or salts because they are both too big to pass through. Graphene is stronger than the epoxy-GO used here and would be easier to make if you can control the pore size. Seems like Lockheed figured this one out years ago. So where is it, Lockheed?

Anyway, some time in the near future, with or without Lockheed, there will be some nanomaterial carbon filter desalinating water. I guess that should be the good news.

Clean water...

nm

a reply to: TEOTWAWKIAIFF

Ty.

You should get the flags and stars. lol

a reply to: UpIsNowDown

If this does what it says on the tin and turns out to be cost effective its going to go a long way as to the betterment of humanity given the fact that new fresh water sources are becoming rather few and far between.

That being said i imagine there may be more than just salt that would have to be removed from our sea water before it's safe for mass human consumption especially if we keep dumping the things we do into our oceans.

Seems water purification is all the rage among the material scientists this week!

"We know carbon as graphite for our pencils, as diamonds, as soot," Rocha said. "We can transform that soot or graphite into a nanometer-type material known as graphene."

A single-walled carbon nanotube is created when a sheet of graphene is rolled up. The physical change alters the material's chemical structure and determines how it behaves. The result is "one of the most heat conductive and electrically conductive materials in the world," Rocha said. "These are properties that only come into play because they are at the nanometer scale."

"We have shown that we can regenerate these materials," said Rogers... "In the future, when your water filter finally gets saturated, put it in the microwave for about five minutes and the impurities will get evaporated off."

ScienceDaily.com, March 29, 2017 - Reusable carbon nanotubes could be the water filter of the future, says study.

They want to use this filter on polluted water. I am not sure about "throw it in the microwave" aspect. Seems that if you have lead in the water that gets trapped in the CNT sponge you would want to carefully remove it and not re-contaminate the environment.

This is nowhere near as far along as the OP's sieve. But it sounds like a good way to clean water and that is good for all.



a reply to: Bleeeeep

LOL. It is science for the betterment of mankind. Who cares about stars and flags!? Thanks for the sentiment, though. It would be great to not fight wars over clean water. We do need to clean up our mess of a planet.

a reply to: TEOTWAWKIAIFF

Thanks from myself also for the massive addition of information

Star and flag also, stop blushing

Graphene-oxide membranes have attracted considerable attention as promising candidates for new filtration technologies. Now the much sought-after development of making membranes capable of sieving common salts has been achieved.

New research demonstrates the real-world potential of providing clean drinking water for millions of people who struggle to access adequate clean water sources.

The new findings from a group of scientists at The University of Manchester were published in the journal Nature Nanotechnology. Previously graphene-oxide membranes have shown exciting potential for gas separation and water filtration.

Graphene-oxide membranes developed at the National Graphene Institute have already demonstrated the potential of filtering out small nanoparticles, organic molecules, and even large salts. Until now, however, they couldn’t be used for sieving common salts used in desalination technologies, which require even smaller sieves.
Watch more graphene related videos at www.youtube.com...

This really could be a game changer, i would imagine it needs more work to produce the materials required in a cost effective manner but its more than worth the time, effort and cost.

Once we begin to seriously run low on fresh drinking water things are going to get real bad real quick, think oil wars x 1000.

This gives some hope for the future though, the human race really can achieve anything when we try its just a shame all nations cant put aside petty political and ideological differences and work together on things like this.

We can hope and dream though i suppose

Wasn't there a thread on a cement factory attachment that makes this stuff?

Anyway, cheap desalination would be great!

Taken directly from the paper:



Quote

The salt rejection properties of our GO–Gr membranes were further investigated using
forward osmosis, where we employed concentrated sugar (3 M) and
NaCl (0.1 M) solutions as the draw and feed solutions, respectively
(Supplementary Section 7). ..
are the concentration of NaCl at the draw and
feed sides, respectively. Our analysis yielded ≈97% salt rejection
for the GO–Gr membranes with a water flux of ≈0.5 l m–2 h–1
.
Even though the flux is lower than 5–10 l m–2h–1 typical for
forward osmosis, we believe this characteristic can be significantly
improved by decreasing the membrane thickness to 1 µm or less
(Supplementary Section 7). Such thicknesses are readily achievable
for GO laminates and can result in fluxes >5 l m–2h–1



www.nature.co...r...=www.bbc.co.uk

IMO, we now have a good solution for desalination of water using a relatively cheap material (graphene oxide) but the flow rates depend on single salt solutions in controlled experiments where the flow rate achieved is approximately 5 litres per metre squared per hour. You can use thousands of graphene oxide membranes simultaneously to get a reasonable flow rate. However, the amounts of different salts and biological materials would need a pre-filter that would slow down the flow rate. Is it possible to give an impoverished coastal town with sufficient clean water for their drinking needs? I don't know - I am not an engineer or a materials scientist. However, I am sure there are such people on the forum who can chip in on this important matter.

a reply to: TEOTWAWKIAIFF

I was originally looking for an article about some new polymer pipe that seeps pure water to the outside, while trapping salt as a solid on the inside, to be cleaned out or flushed.
It doesnt take ultra high pressure, and is an easily mfgd,
But, i found this instead,

The material, a nanometer-thick sheet of molybdenum disulfide (MoS2) riddled with tiny holes called nanopores, is specially designed to let high volumes of water through but keep salt and other contaminates out, a process called desalination. In a study published in the journal Nature Communications, the Illinois team modeled various thin-film membranes and found that MoS2 showed the greatest efficiency, filtering through up to 70 percent more water than graphene membranes.

www.sciencedaily.com...

That is fascinating stuff, MoS2 is a common high pressure ingredient in industrial lubricants.

all this technology i see trying to fix overpopulation created problems like this will only make things worse or just delay them, make people complacent and prevent social evolution to change our wasteful ways and learn control of ourselves.

our lack of control is the problem but until people understand this and stop blaming everything else except themselves, nothing will help us save ourselves not even our best technology.

we have way too many people to feed, hydrate and clean after, making population easier to sustain and grow faster will not fix anything at all.

originally posted by: Bleeeeep
a reply to: TEOTWAWKIAIFF

Ty.

You should get the flags and stars. lol

Lol, only just noticed this and can only agree %100, most of the best threads on ATS are posted by TEOTWAWKIAIFF

a reply to: punkinworks10

I started thread on nothing but Transition Metal Dichalcogenides because it is a very wide open and interesting topic! It is over in the science forum. Add news as you run across it (I kind of view it as a Quake Watch type thread where anybody can contribute what they like).

a reply to: UpIsNowDown

Aw, shucks!

Being a nerd takes a lot of explaining! Which of course is one method of learning something. If you can explain a difficult subject to yourself, and help somebody else understand who is not as "up to speed" as you are, understand, then you probably have a decent understanding of the subject.