Another tiny miracle: Graphene oxide soaks up radioactive waste

Jan 08, 2013
A new method for removing radioactive material from solutions is the result of collaboration between Rice University and Lomonosov Moscow State University. The vial at left holds microscopic particles of graphene oxide in a solution. At right, graphene oxide is added to simulated nuclear waste, which quickly clumps for easy removal. Credit: Anna Yu. Romanchuk/Lomonosov Moscow State University

(Phys.org)—Graphene oxide has a remarkable ability to quickly remove radioactive material from contaminated water, researchers at Rice University and Lomonosov Moscow State University have found.

A collaborative effort by the Rice lab of chemist James Tour and the Moscow lab of chemist Stepan Kalmykov determined that microscopic, atom-thick flakes of graphene bind quickly to natural and human-made radionuclides and condense them into solids. The flakes are soluble in liquids and easily produced in bulk.

The experimental results were reported in the journal Physical Chemistry Chemical Physics.

The discovery, Tour said, could be a boon in the cleanup of contaminated sites like the Fukushima damaged by the 2011 earthquake and tsunami. It could also cut the cost of ("fracking") for oil and gas recovery and help reboot American mining of rare earth metals, he said.

's large surface area defines its capacity to adsorb toxins, Kalmykov said. "So the high retention properties are not surprising to us," he said. "What is astonishing is the very fast kinetics of sorption, which is key."

"In the probabilistic world of chemical reactions where scarce stuff (low concentrations) infrequently bumps into something with which it can react, there is a greater likelihood that the 'magic' will happen with graphene oxide than with a big old hunk of bentonite," said Steven Winston, a former vice president of Lockheed Martin and Parsons Engineering and an expert in nuclear power and remediation who is working with the researchers. "In short, fast is good."

Determining how fast was the object of experiments by the Kalmykov group. The lab tested graphene oxide synthesized at Rice with simulated nuclear wastes containing uranium, plutonium and substances like sodium and calcium that could negatively affect their adsorption. Even so, graphene oxide proved far better than the bentonite clays and granulated activated carbon commonly used in nuclear cleanup.

Graphene oxide introduced to simulated wastes coagulated within minutes, quickly clumping the worst toxins, Kalmykov said. The process worked across a range of pH values.

"To see Stepan's amazement at how well this worked was a good confirmation," Tour said. He noted that the collaboration took root when Alexander Slesarev, a graduate student in his group, and Anna Yu. Romanchuk, a graduate student in Kalmykov's group, met at a conference several years ago.

The researchers focused on removing radioactive isotopes of the actinides and lanthanides – the 30 rare earth elements in the periodic table – from liquids, rather than solids or gases. "Though they don't really like water all that much, they can and do hide out there," Winston said. "From a human health and environment point of view, that's where they're least welcome."

Naturally occurring radionuclides are also unwelcome in fracking fluids that bring them to the surface in drilling operations, Tour said. "When groundwater comes out of a well and it's radioactive above a certain level, they can't put it back into the ground," he said. "It's too hot. Companies have to ship to repository sites around the country at very large expense." The ability to quickly filter out contaminants on-site would save a great deal of money, he said.

He sees even greater potential benefits for the mining industry. Environmental requirements have "essentially shut down U.S. mining of , which are needed for cell phones," Tour said. "China owns the market because they're not subject to the same environmental standards. So if this technology offers the chance to revive mining here, it could be huge."

Tour said that capturing does not make them less radioactive, just easier to handle. "Where you have huge pools of radioactive material, like at Fukushima, you add graphene oxide and get back a solid material from what were just ions in a solution," he said. "Then you can skim it off and burn it. Graphene oxide burns very rapidly and leaves a cake of radioactive material you can then reuse."

The low cost and biodegradable qualities of graphene oxide should make it appropriate for use in permeable reactive barriers, a fairly new technology for in situ groundwater remediation, he said.

Explore further: Graphene sensor tracks down cancer biomarkers

More information: pubs.rsc.org/en/Content/Articl… g/2013/CP/C2CP44593J

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User comments : 16

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tekram
not rated yet Jan 08, 2013
"Cation/GO coagulation occurs with the formation of nanoparticle aggregates of GO sheets, facilitating their removal. GO is far more effective in removal of transuranium elements from simulated nuclear waste solutions than other routinely used sorbents such as bentonite clays and activated carbon. "
About 10x more adsorptive than bentonite clay, 35x more than activated carbon for transuranium elements.
HTK
1 / 5 (4) Jan 08, 2013
hmm... mission to mars now possible?
extinct
2 / 5 (8) Jan 08, 2013
you would think that they'd be eager to roll out such technologies for Fukushima and the Pacific Ocean which is now widely contaminated with radioactivity. and you'd be wrong! if there's no money in a humanity-friendly technology for a psychopath investor, that technology will never be utilized. money: the root of all evil.
tekram
4 / 5 (4) Jan 08, 2013
Bentonite cost about $35 per ton. I don't think you can make GO (graphene oxide) for $35 per pound.

On the other hand, GO is probably very good for gold recovery from gold slurry after cyanidation leaching. So, yes, money is the root of all evil, but gold beats them all.
indio007
2.3 / 5 (3) Jan 08, 2013
Why have this when you can have this.

http://www.dotmed...ry/10571
In mice, when Dr. Isenberg and his team introduced a drug that prevented a protein, thrombospondin-1, from binding to a surface cell receptor called CD47, the animals could endure almost unheard-of doses of radiation with virtually no ill effects.

In cellular studies, cells could withstand up to the tested amount: 60 Gy. And in whole animal studies, mice could endure the limit they were given: 40 Gy.
MS4260
3 / 5 (6) Jan 08, 2013
Correction: The LOVE of money is the root of evil. Money itself is neither good nor evil.
Caliban
1 / 5 (1) Jan 08, 2013
Not a cure, by any stretch, but at least a method for cleaning up and recycling radioactive waste.

But this begs the question of what to do with it once reclaimed.
Caliban
5 / 5 (1) Jan 08, 2013
Why have this when you can have this.

http://www.dotmed...ry/10571
In mice, when Dr. Isenberg and his team introduced a drug that prevented a protein, thrombospondin-1, from binding to a surface cell receptor called CD47, the animals could endure almost unheard-of doses of radiation with virtually no ill effects.

In cellular studies, cells could withstand up to the tested amount: 60 Gy. And in whole animal studies, mice could endure the limit they were given: 40 Gy.


@indio007,

That's great news for cases of acute exposure, but since most damage caused by radiation is from bio-persistence, then this most likely isn't going to have any use other than as treatment for acute exposure, since there is little likely doubt that long term suppression of this pathway would probably have severe negative health effects.
Shootist
2.3 / 5 (3) Jan 09, 2013
and the Pacific Ocean which is now widely contaminated with radioactivity.


Are you young, uneducated, unread, unthinking, illogical or, how many standard deviations below the mean are you, anyway?

Buckwheat, 50-60 years ago, we detonated hundreds of nuclear warheads, above, on and below the ocean's surface. One little bitty Nipponese fission reactor isn't going to get anyone but an idiot's attention.
Caliban
not rated yet Jan 09, 2013
Bentonite cost about $35 per ton. I don't think you can make GO (graphene oxide) for $35 per pound.

On the other hand, GO is probably very good for gold recovery from gold slurry after cyanidation leaching. So, yes, money is the root of all evil, but gold beats them all.


Since they don't provide any hard numbers for the adsorption per unit weight in terms of the GO's adsorptive capacity, then it is pretty difficult to say this with any degree of certainty.

It does seem likely, however, that we will see a continued decline in the cost of various graphene materials --GO presumably included-- as production of these incredibly useful materials is scaled up to meet increasing demand.

Further, it is conceivable that at some point, the amount of GO required to adsorb an equivalent amount of RAIs might actually become less than the cost for the required amount of Bentonite.

yep
1 / 5 (3) Jan 09, 2013
Hemp is good for radioactive waste clean up, and it is inexpensive unless you live under prohibition.
http://www.mhhe.c..._10.html
antialias_physorg
5 / 5 (2) Jan 09, 2013
you would think that they'd be eager to roll out such technologies for Fukushima and the Pacific Ocean which is now widely contaminated with radioactivity. and you'd be wrong!
I'd think the reason something like this isn't going to be deployed is because the Pacific Ocean (or even the 'small' part around Fukushima) is a rather HUGE volume of water - wouldn't you think?
We're not talking a few liters (or even megaliters), here. The Pacific Ocean contains roughly 8E21 liters (that's 8 trillion billion liters).
alfie_null
not rated yet Jan 09, 2013
Hemp is good for radioactive waste clean up, and it is inexpensive unless you live under prohibition.

I'm guessing more often than not it's not practical to plant and grow a bunch of cannabis where the contamination exists.
katesisco
1 / 5 (2) Jan 09, 2013
First, thanks for the comment site, other sites are folding their comments up.
Second, with all natural remediation of radiation (sunflowers, hemp, and especially vetiver root (look it up) the product itself is radioactive which really just moves the problem along and the solution burning just puts radioactivity back into the air. This GO burning produces a cake that has to be disposed of---claiming a use is facetious.
The fact that India used a series of lagoons to filter waste from Delhi BEFORE it was improved by the Brits should give you some idea of the current status of technology. Salt water marshes are natural filters and algea has been engineered to acquire a taste for radioactivity but again http://www.enviro...s/all/1/ and algae are consumed if at sea and again burned/buried/when used to decon water.
I have heard coal burners compared to nuke plants with the nuke plants coming out with a cleaner record.
yep
1 / 5 (3) Jan 10, 2013
Well you guessed wrong. Cannabis is very practical and is utilized. The process is called Phytoremediation and not only is it effective for uranium, cesium-137, strontium-90, it also works for heavy metals like lead, pesticides, solvents, explosives, crude oil, polyaromatic hydrocarbons and leaching landfill toxins. So if you do not want to turn it into fuel because your worried about putting it in the air then make it into hempcrete for roads or bridges. We have some of those still being used from the sixth century.
packrat
1 / 5 (1) Jan 12, 2013
So what's to stop some terrorist jerk from drilling two wells in an area that has a lot of radioactive materials though not enough in concentration for mining to pump water from one to the other and using this stuff to concentrate enough radioactive materials together to create a dirty atomic type bomb? This is something radical nutcases would probably really like to hear about.