Uranium from seawater factors into nuclear power

Uranium from seawater factors into nuclear power
Postdoctoral scholar Chong Liu examines a carbon-amidoxime electrode as part of research to improve extraction of uranium from seawater. Credit: L.A. Cicero

Trace amounts of uranium exist in seawater, but efforts to extract that critical ingredient for nuclear power have produced insufficient quantities to make it a viable source for those countries that lack uranium mines. A practical method for extracting that uranium, which produces higher quantities in less time, could help make nuclear power a viable part of the quest for a carbon-free energy future.

"Concentrations are tiny, on the order of a single grain of salt dissolved in a liter of water," said Yi Cui, a materials scientist and co-author of a paper in Nature Energy. "But the oceans are so vast that if we can extract these trace amounts cost effectively, the supply would be endless."

Alternative forms of like wind or solar are critical for reducing the world's carbon emissions. While wind and solar costs are plunging, some experts argue that nuclear power remains important because it can be turned on and off to match peaks and valleys in demand without carbon emissions.

"We need nuclear power as a bridge toward a post-fossil-fuel future," said Professor Steven Chu, a Nobel Prize-winning physicist and co-author of the Nature Energy article. "Seawater extraction gives countries that don't have land-based uranium the security that comes from knowing they'll have the raw material to meet their energy needs."

Chu, a former U.S. secretary of energy who encouraged seawater extraction research before he left the Department of Energy (DOE) to return to Stanford, observed that nuclear power currently generates 20 percent of U.S. electricity and 13 percent worldwide. Even as researchers work to improve reactor safety and solve the issues, he believes that a practical way to extract uranium from seawater is needed to reduce the energy insecurity of nations that depend on nuclear power but lack uranium within their own borders.

Improved extraction

The Stanford findings build on years of research in Japan and China, as well as by DOE scientists at Oak Ridge National Laboratory and the Pacific Northwest National Laboratory.

Scientists have long known that uranium dissolved in seawater combines chemically with oxygen to form uranyl ions with a positive charge. Extracting these uranyl ions involves dipping plastic fibers containing a compound called amidoxime into seawater. The uranyl ions essentially stick to the amidoxime. When the strands become saturated, the plastic is chemically treated to free the uranyl, which then has to be refined for use in reactors just like ore from a mine.

How practical this approach is depends on three main variables: how much uranyl sticks to the fibers; how quickly ions can be captured; and how many times the fibers can be reused.

In the recent work, the Stanford researchers improved on all three variables: capacity, rate and reuse. Their key advance was to create a conductive hybrid fiber incorporating carbon and amidoxime. By sending pulses of electricity down the fiber, they altered the properties of the hybrid fiber so that more uranyl ions could be collected.

Better, faster, longer lived

Postdoctoral scholar Chong Liu oversaw the lab tests that compared Stanford's amidoxime-carbon hybrid fibers with today's amidoxime fibers. First she tested how much uranyl each type of fiber could hold before reaching saturation. In these tests she found that by the time the standard amidoxime fiber had become saturated, Stanford's amidoxime-carbon hybrid fibers had already adsorbed 9 times as much uranyl and were still not saturated. What's more, the electrified fiber captured three times as much uranyl during an 11-hour test using seawater from Half Moon Bay, about an hour from Stanford, and had three times the useful lifespan of the standard amidoxime.

"We have a lot of work to do still but these are big steps toward practicality," Cui said.

Chu emphasized that research on seawater extraction has to proceed in parallel with reactor safety and waste disposal challenges. "For much of this century, some fraction of our electricity will need to come from sources that we can turn on and off. I believe should be part of that mix, and assuring access to is part of the solution to carbon-free energy," he said.


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New technique could lead to safer, more efficient uranium extraction

Journal information: Nature Energy

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Feb 20, 2017
because it can be turned on and off to match peaks and valleys in demand without carbon emissions.

Well, it can't really be turned on or off that quickly. Nuclear powerplants have quite some run-up time. And they don't even help as backup, because they need to be backed up themselves (they need to be taken offline when the weather gets too hot or they are down for inspections/repairs).

Investing in some storage solutions for excess renewable energy sounds like a lot better strategy to me. (Not even taking the environmental/safety issues into account).

Feb 20, 2017
Well, it can't really be turned on or off that quickly. Nuclear powerplants have quite some run-up time.


Depends on the size and construction.

(they need to be taken offline when the weather gets too hot or they are down for inspections/repairs).


Again depends on the size and construction.

Investing in some storage solutions for excess renewable energy sounds like a lot better strategy to me


Again depends on the size and construction.

It's easy to pitch these options against each other without specifying what exactly do you mean by nuclear power, or by storage solutions. France runs a number of nuclear powerplants in load following mode, and most storage solutions are ridiculously expensive or simply unavailable in greater amounts.

The economics of nuclear powerplants are such that you don't save anything by throttling them down, so they're allowed to run constantly and the excess is dumped somewhere somehow.

Feb 20, 2017
In fact, according to the NEA:

The minimum requirements for the manoeuvrability capabilities of modern Generation III/III+ reactors are defined by the utility requirements which are based on the requirements of the grid operators. According to the current version of the European Utility Requirements (EUR) the NPP must be capable of a minimum daily load cycling operation between 50% and 100% Pr, with a rate of change of electric output of 3-5% Pr/minute.


Gen II reactors were also built with extensive load following capacities, but they didn't have such standard requirements so it varies between make and model.

Running them in load following mode simply costs more because the costs of running a nuclear power station are more or less fixed regardless of output, so if possible they're run at full output and the excess power is sold at a loss - that's better than making nothing.

Feb 20, 2017
(response to AntiAlias_PhysOrg)
That's exactly backwards: from the excellent wikipedia article on the physics of nuclear power:

"Furthermore, increases in reactor power can be performed at any desired rate simply by pulling out a sufficient length of control rod. However, without addition of a neutron poison or active neutron-absorber, decreases in fission rate are limited in speed, because even if the reactor is taken deeply subcritical to stop prompt fission neutron production, delayed neutrons are produced after ordinary beta decay of fission products already in place, and this decay-production of neutrons cannot be changed."

Feb 20, 2017
One can imagine a future time when ship-cities travel around extracting uranium from the oceans to feed their reactors.
http://freedomship.com/
http://www.scienc...ing-city

Feb 20, 2017
From ornl.gov

"Recent testing exceeded 6 grams of uranium per kilogram of adsorbent after 56 days in natural seawater..."

That's about the same as an ore that is about 0.5% uranium. Because adsorption is specific, and extraction is equally specific, the costs of obtaining refined natural uranium might be favorable. The best ores are Canadian, at between 17 and 18% uranium oxide.

I am thankful for the vital work done by our national laboratories. No for-profit business can justify the kind of research done there.

Feb 20, 2017
Why don't they just BUY Uranium from Australia? The land of Oz has heaps of the stuff. Now if Australia won't sell it to a particular country, then perhaps there is an INTERNATIONAL reason for this, and thus we should not be encouraging those rogue states to extract it from sea water in the first place.

Feb 21, 2017
Why don't they just BUY Uranium from Australia?

Why buy when you can make it yourself? Makes you independent of the buyer. People who sell something (particularly if they are one of only a few producers) tend to use that to their own ends. Either by political pressure or just simple price hikes. Look at the history of oil.

those rogue states

The problem is always: who defines who is 'rogue'? Does e.g. Iran have a right to develop a nuclear energy program (or nuclear weapons) - and if not, why not? (and if not - why do others have that right?). Those are tricky questions because there's no real good argument to forbid it to them if we, at the same time, say it's OK for others to have them.
We run into hypocrisy real fast.

(Note: I wouldn't like Iran to have nukes. But for the life of me I can't find a *good* argument to forbid them from having them that wouldn't also apply to every other nation that already has them)

Feb 21, 2017
there's no real good argument to forbid it to them


There's a simple checklist whether a country should not be permitted nuclear weapons:
- ruled by authoritarian regimes
-severily restricts human rights
-sponsors terrorism
-seeks to use weapons of mass destruction against its neighbors

The point is that some nations aren't governed by rational regimes that seek the nation's best interest in the international arena, but instead follow the whims and machinations of a despotic leadership whether it be a communist dictator or some deeply religious junta etc. and that makes them unpredictable and unreasonable, unable to be reasoned with by diplomacy.

It's the international equivalent of a loony on the street with a knife or a gun. They may have a reason to be acting violently, but it's not helping their case, and the only real remedy is to take the weapon away before they hurt people.


Feb 21, 2017
There's a simple checklist whether a country should not be permitted nuclear weapons:

Ok, let's see how these apply to the countries that have nukes:
-- ruled by authoritarian regimes

This disqualifies China, Russia, North Korea and Pakistan.
-severily restricts human rights

This disqualifies China, Pakistan, maybe India. Possibly Russia (also what counts as 'severely' is rather ambiguous)
-sponsors terrorism

Now this one DEFINITELY disqualifies the US - on multiple counts. Also France, Israel, Russia and, possibly, England.
-seeks to use weapons of mass destruction against its neighbors

The US is the only country that did so this is a knock-out for the US (and North Korea, because they have actively said they want to).

See how tricky this is? There's not a single country that would pass that list.

Feb 21, 2017
See how tricky this is?


No, because those countries don't fill all the boxes. They may be authoritarian but they're not belligerent, or they sponsor terrorism but aren't authoritarian etc. In other words, while there's something evil about them, they're still being reasonable and respond to diplomacy.

Well, except China and Russia, which are both authoritarian, both support terrorism, both belligerent and both severily restrict human rights. They're just too big to do anything about, especially because they already have nuclear weapons.

The US is the only country that did so this is a knock-out for the US


"Seeks to use" means they actively want to attack and are just itching to go. There are some warmongers in the US for sure, but as an entity it's not belligerent in the same sense that North Korea is.

Of course you can come up with all sorts of fantasies about how the US is a "capitalist imperialist invader", but that's just propaganda rhetoric.

Feb 21, 2017
The point is that when a country like the US gets caught supporting terrorism, it's red faces all around and they take a diplomatic hit: they have to concede that they did wrong and try to repair the damage. They respond to the international community.

The rogue states simply don't care. They'll push the envelope, do whatever they like, and essentially troll the international community to the point of war, and then act like they're the victims:

https://kilburnha...and1.jpg

That's what's Iran is doing, what North Korea is doing, what Russia is doing...

Feb 21, 2017

(Note: I wouldn't like Iran to have nukes. But for the life of me I can't find a *good* argument to forbid them from having them that wouldn't also apply to every other nation that already has them)
Its FUNNY how people like aa can somehow think that moral authority alone is enough to convince rogue regimes and lunatics from developing the weapons to destroy you.

"You cant do it because its BAD."

How the HELL would that work?

"If you develop nukes we will attack you."

1 year later:

"We have many of our evil nukes sitting in your harbors. Do we feel bad about that? No we feel pretty good about that."

What an idiot.

Feb 21, 2017
There's a simple checklist whether a country should not be permitted nuclear weapons
North korea is not permitted to have nuclear weapons.

Jesus fucking christ.

People like aa would want us to drop our pants, point our buttholes at the enemy, and say "see how morally superior we are?"

Guess what happens next?

Feb 21, 2017
People like aa would want us to drop our pants, point our buttholes at the enemy, and say "see how morally superior we are?"


It's not your enemy, unless you're from Israel or South-Korea. We don't really have anything to do with other people's conflicts per se - the point is simply that handing two opposing zealots nuclear weapons isn't "fair play" - it's just dumb.

Feb 21, 2017
We don't really have anything to do with other people's conflicts per se
Another isolationist I see. North koreas nukes are pointed at us. The soviet and chinese nukes were pointed at us. And the certain knowledge that they would inevitably have them is why we needed to develop them first.

An israeli/iran nuclear exchange would obviously affect us directly, as would an india/pakistan exchange. And coordinated preemptive attacks against these 2 countries as a precursor to founding a moslem empire, would certainly threaten us directly. Which us why we are allies.
the point is simply that handing two opposing zealots nuclear weapons isn't "fair play" - it's just dumb
The point is, the only way to deter their use is to present an absolute threat of annihilation should they be used. There is no way of guarantering that we could successfully invade a nuclear-armed country and disarm them. But we could obliterate them remotely and they need to know that.

Feb 21, 2017
means they actively want to attack and are just itching to go. There are some warmongers in the US

Since the current president of the US has declared that he sees no reason why not to use nukes...what was your point exactly? Hard to get a higher level of war-mongery than from the CINC.

"itching to go" is also a pretty vague term. How *exactly* do you define this (in a court of law). ..."Your honor : the defendant was itching to use nukes, but he didn't. Therefore we should not let him have any"...I don't see how that can work.

Well, except China and Russia

Israel? Pakistan? US? C'mon...the CIA is propping up terrorist groups and dictators left and right (they trained and supplied the friggin' Taliban for Chrissakes....or Iran-Contra? Is this stuff no longer taught in history class?)
The list of US sponsored terrorist organizations is one of the longest pages on wikipedia
https://en.wikipe...errorism

Feb 21, 2017
Since the current president of the US has declared that he sees no reason why not to use nukes...what was your point exactly?


Exactly that. Certain nations are not "rogue" as they are, but because of how they behave. While certain Republicans surely would like to turn the middle east into glass, that's not an offical US policy, and other nations certainly still have their say on the matter through diplomatic relationships. If Trump goes solo and starts playing dictator, the US system -should- work to remove him from power.

How *exactly* do you define this


I would say some sort of implicit or explixit declaration of intent would be required, such as Iran making the statement that it doesn't recognize Israel as a country, and funding terrorist organizations that aim to remove said country.

Israel? Pakistan? US? C'mon..


I'm not arguing the US hasn't supported terrorists, I'm saying that alone isn't sufficient to label the US a rogue state.

Feb 21, 2017
Since the current president of the US has declared that he sees no reason why not to use nukes
I am pretty sure trump would never use a double negative. But his views on nuke use are the same as obamas

"But in the end, Mr. Obama seems to have sided with his current advisers, who warned in meetings culminating this summer that a no-first-use declaration would rattle allies like Japan and South Korea."

-even if he is more open and clear about it.

Aa's views are obviously colored by a healthy hate of everything US. No rational discussion possible.

Feb 21, 2017
The soviet and chinese nukes were pointed at us. And the certain knowledge that they would inevitably have them is why we needed to develop them first.


The question here is of rogue states, not cold war. Cold war and MAD is an example of rationally behaving states that see the balance and calculate that they don't want to start a nuclear war.

Rogue states is about states who couldn't give a crap if they start WW3 as long as they get to turn their immedate enemies into ash. It's about regimes that are no longer acting rationally with even their own interest in mind, instead acting on some religious dogma or petty vengeance etc.

The point is, the only way to deter their use is to present an absolute threat of annihilation


That's the problem. The rogue states do not necessarily respond to that threat: they're banking on the knowledge that nobody actually wants to start total global annihilation - that everybody is just posing. Or they're just mad.

Feb 21, 2017
Another isolationist I see.


I'm not an isolationist or an interventionist. I don't think the US or the UN or anyone has the right to barge in to other peoples conflicts and "solve" them in ways that align with their own interests. These matters should be handled mutually.

That's part of the problem, and it's exactly the reason why any use of nuclear weapons would be instant suicide by everyone, because everyone is aligned with someone and when Israel nukes Iran or vice versa, the whole house of cards collapses. Nobody wants that to happen, except those who just want to watch the world burn - the rogue states.


Feb 21, 2017
I'm not an isolationist or an interventionist. I don't think the US or the UN or anyone has the right to barge in to other peoples conflicts and "solve" them in ways that align with their own interests. These matters should be handled mutually
This was the argument used by isolationists to keep us out of the german/russian war. But had we not landed in normandy, europe would have undoubtedly ended up communist.

I think you are being overly naive and simplistic. This is a very small world. Nothing happens without affecting everybody. Right now a caliphate is a distinct threat. Supporting allies who are actively fighting against islamism, and fighting it ourselves, is a necessity.

And supporting nuclear-armed allies is imperative. Things can change very quickly. Pakistan could fall, iran could get nukes, north korea could ally with both to attack simultaneously.

We need to be prepared to respond with nukes if necessary.

Feb 21, 2017
That's part of the problem, and it's exactly the reason why any use of nuclear weapons would be instant suicide by everyone, because everyone is aligned with someone and when Israel nukes Iran or vice versa, the whole house of cards collapses
How do you figure? The western coalition invaded iraq twice and the world didnt end. The idea that nukes are some mythical Armageddon beast that would make everybody want to fight everybody is just another lie left over from ww1 secret treaties.

The only reason iraqi allies didnt join in husseins defence is because of the nuclear deterrant.

We can obliterate rogue nations just like we obliterated hussien but to do so against nuclear-armed nations requires nukes.

Feb 21, 2017
More importantly - in order to be able to demand with authority that nations give up nukes, youve got to be able to threaten them with nukes. Theyve got to know that their nukes will never be able to protect them.

Feb 21, 2017
This comment has been removed by a moderator.

Feb 21, 2017
would like to turn the middle east into glass, that's not an offical US policy

Ya know - here I was thinking that the official US policy was set by the united states department of state. ...head of which is the secretary of state...which is appointed by - hold on to your hats - the president. Soooo....yeah. The president is pretty much instrumental in setting official US policy, I'd say.

such as Iran making the statement that it doesn't recognize Israel as a country

Not recognizing a state is not the same as saying "I'm gonna nuke you". (note that the US has a list of states it doesn't recognize, too. So this isn't particular to Iran).

As for funding terrorists and setting up friendly dictators (i.e. not recognizing nations/heads of state) by the US...you really, REALLY don't wanna go there.

Feb 21, 2017
"North koreas nukes are pointed at us. "
--------------------------------

No, they're not. They have none which can be mounted on missiles yet.
It is like when you were screaming "WMD!". You are just SCARED.

That is why you get so abusive. It is pathetic FEAR.

"WMD!"!!

Is he still here?

Feb 21, 2017
In the end there's always the elephant in the room: Would they use nukes?

And the most damning evidence of this is: "have they used nukes in the past?" And the only nation that this goes for is the US.

Face it: whatever definition of 'rogue' or 'unworthy of nukes' you construct: The US fits it on a lot grander scale than any nation on the planet.

So while I have no problem with a policy that would stop e.g. Iran from gaining nukes we should dispense with the moral angle.
The real reason is: "because a - by most any category you care to name - more evil empire says so"

That would at least be honest.

Feb 21, 2017
"North koreas nukes are pointed at us. "
--------------------------------

No, they're not. They have none which can be mounted on missiles yet.
It is like when you were screaming "WMD!". You are just SCARED.

That is why you get so abusive. It is pathetic FEAR.

"WMD!"!!

Is he still here?
Sorry I dont engage with lying cheating psychopaths.

Try baiting somebody else.

Feb 21, 2017
And the most damning evidence of this is: "have they used nukes in the past?" And the only nation that this goes for is the US
Well we could use the same argument about germany and gas chambers. Nicht wahr?

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