Introducing the Gizmag Store

Oak Ridge develops improved way of extracting uranium from seawater


August 22, 2012

A disc of highly enriched uranium from the Y-12 National Security Complex Plant

A disc of highly enriched uranium from the Y-12 National Security Complex Plant

The world’s estimated reserves of uranium are only 6 million tons and with the growing demand for reliable energy free of greenhouse emissions leading to more and more nuclear plants being built, that supply may not last very long. Some estimates place the time before all the uranium is gone at between 50 and 200 years. However, the oceans of the world contain 4.5 billion tons of uranium dissolved in seawater. That’s enough to last something on the order of 6,500 years. The tricky bit is getting it out, but a team at Oak Ridge National Laboratory, Tennessee has come a step closer to economically extracting uranium from seawater with a new material that is much more efficient than previous methods.

Ever since it was learned how much precious metal is dissolved in seawater, scientists, engineers, visionaries and con men have dreamed of ways to extract it. In the 1920s, popular science editor Hugo Gernsback graced the covers of his magazines with fanciful floating factories hauling giant sheets of gold out of the briny deep. Since the 1960s, almost a dozen nations have studied ways of making the dream a reality. The Japanese have been particularly successful with the the Japan Atomic Energy Research Institute having some success in extracting uranium using mats of woven polymer fibers in 2002, but at a cost three times the market price of the metal at the time. That is the basic problem – you can get the metal out, but it costs more than it’s worth.

Now a team at Oak Ridge is working to bring down those costs by devising a more efficient method of extraction. The Oak Ridge team’s approach is based on their examination of how plastic and chemical groups are bound together. From this, they determined that it was possible to enhance the uranium-extracting characteristic of the uranium-loving amidoxime chemical groups in their high-capacity reusable adsorbent, which they combined with a Florida company's high-surface-area polyethylene fibers. These fibers have a small diameter with high surface areas and a variety of shapes. Tailoring the size and shape of the fibers increases their adsorption capacity. The fibers are bombarded with radiation, which react with chemicals that have a high affinity for particular metals. The result is a little uranium sponge.

Using the material, called Hicap, is simply a matter of immersing it in seawater. As it sits in the water, the material grabs on to the uranium ions and deposits them on the surface of its fibers. Once a sufficient amount of uranium is adsorbed, the material is removed and the metal extracted with acid. "We have shown that our adsorbents can extract five to seven times more uranium at uptake rates seven times faster than the world's best adsorbents," said Chris Janke, one of the inventors and a member of Oak Ridge’s Materials Science and Technology Division. HiCap is also reusable as, after the extraction process, it can be regenerated with potassium hydroxide.

The results of the Oak Ridge team were verified by researchers at Pacific Northwest National Laboratory’s Marine Sciences Laboratory in Sequim, Washington, and were presented a last Wednesday’s meeting of the American Chemical Society in Philadelphia. The material is a long way from making uranium as common as pig iron, but it does demonstrate that extracting it from the oceans may no longer be a con man’s dream.

Sources: Oak Ridge National Laboratory, Pacific Northwest National Laboratory

About the Author
David Szondy David Szondy is a freelance writer based in Monroe, Washington. An award-winning playwright, he has contributed to Charged and iQ magazine and is the author of the website Tales of Future Past.   All articles by David Szondy

With the Japanese method the price of uranium wold have to triple for the process to be commercially viable and this is better. But what is the ratio of isotopes? If it does not need as much enriching that would really alter the real price.

23rd August, 2012 @ 12:08 am PDT

Nuclear power is not close to fossil-fuel free. Currently, it takes over a decade for a Nuke to pay back the power used to build and fuel it, and the future costs are looking even worse, as a tax on all our descendants.

Bob Stuart
23rd August, 2012 @ 03:19 am PDT

1) ...and after that decade you have pure profit and no pollution.

2) as you remove the uranium from sea water, the remaining uranium is diluted making these processing costs increase every day.

2) current uranium reserves 250 years?? Post processing of existing waste stockpiles would last us 10,000 years alone.

Please keep in mind that the amount of uranium actually consumed in nuclear power is only one gallon per 1 million Americans per year. That ratio is based on 100% nuclear power (no more coal, oil or natural gas!). The problem occures when we bury the spent fuel instead of post processing it to remove the still useable fuel.

23rd August, 2012 @ 05:42 am PDT

This is an exciting area of research to use the oceans to extract a variety of costly metals. However, it is expensive for uranium extraction to be viable in the short-term. I commend ORNL for their research.

Currently, there are alternatives to mining uranium that 'mines' the spent fuel by either Plutonium and Uranium Recovery by EXtraction (PUREX), or the Mixed-OXide (MOX) processes. There are pools of spent nuclear fuel in the fuel rods at nuclear power plants waiting final disposition.

23rd August, 2012 @ 08:36 am PDT

no, the 'problem' is -

- 'how to get all the water in all the oceans to go through your uranium filter'

how much energy and time would THAT take?

especially as the concentration dropped..

i assume you can;t divide the ocean into 2 sides:

'filtered' and 'unfiltered'


23rd August, 2012 @ 10:15 am PDT

While this specific objective is commendable a version of this material that could be more broad spectrum and adsorb a range of radioactive isotopes could enable the Russians to detoxify the areas in the Barents and Arctic seas that have been poisoned by Soviet sub reactors as well as to clean up at least some of the real estate devastated around Chernobyl.

It would important for Russia and Ukraine to reduce the excluded area around Chernobyl. It would be fantastic if estimates of abandoning this area declined from 10,000 years to maybe 50 along with a price tag that might be tolerable. After all, parts of Bimini Atoll are still too hot to enter or eat the fish from. It would be great if this kind of problem could go from being insurmountable to being merely a "superfund size problem".

23rd August, 2012 @ 10:42 am PDT

We need to get away from the PBR and BWR reactors that use uranium and go with a safer and more cost effective way of producing electricity like LFTR. A technology that was already developed by Oak Ridge in the 1950's and abandoned because there wasn't enough profitability. It's time we move towards eco friendly solutions. Once again we're going in the wrong direction. It's time to stop lining the pockets of huge corporations and start giving back to the people and the planet.

23rd August, 2012 @ 10:43 am PDT

Thorium is much more common and in a molton salt reactor is much more cost effective and burns nearly 100% of the fuel, so little waste. It is also disaster proof by design. Why are we still talking about Uranium for the future? Go green nukes!

23rd August, 2012 @ 11:59 am PDT

I have to laugh every time I read posts by uranium "experts" saying how easy it is to do this or that or how we should just use thorium like every energy expert out there is a complete fool for not doing so!

Come on, every option is carefully examined and if it is practical and the costs are less than other alternatives, it is used. Period.

Maybe in 3-5 years (that's what every scientists says so they can get more funding yet less than 1% of the claims ever pan out to become a useful technology - devil is in the details) we will have this new method but for today the costs for uranium are going up and the reserves are going down and the concentrations are getting lower (more energy needed to extract the same amount of useful product = less net energy).

It is still a non-renewable resource and is expected to peak in less than 20 years, at the current rate of use. Read that again - current rate of use. For those nuclear fanboys who want every country on Earth to build more nuclear plants, the more you build, the faster the resource is used up. Many forget this point because it hurts their position.

Both the third and forth largest economies in the world (Japan and Germany) and arguably the two most technologically advanced are giving up on nuclear power. Completely. Think about that, forum experts. Why would they do that if the solutions were so cheap and simple? They wouldn't. The US would be building new plants and using thorium but they are not. Why? Because they already tried them! The costs were too high.

The US can no longer afford to spend the crazy amounts of capital needed for new nuclear plants and technologies. The nuclear industry is near dead and it will stay that way.

Now if these guys are right and they find a way to have almost unlimited fuel at competitive prices then maybe but don't count on it until the fuel is on the market at high volumes. Maybe in 10 years... Then add 10 - 20 more years to where the new reactors are build and we may just have good electricity prices. I am not crossing my fingers yet. I want proof and real cost data.

Oh, finding a cost effective way to get rid of our spend waste would also need to be resolved. It isn't sustainable if you don't take care of the waste.

23rd August, 2012 @ 02:02 pm PDT

Nobody has put any serious investment into Thorium, only a miniscule fraction of what's been invested in other nuclear solutions. Thorium also has a major 'disadvantage' in that it doesn't provide material for nuclear weapons, so there is no military or political incentive (and matching military-sized budget) to get the job done.

Thorium is certainly promising but, despite many wildly optimistic claims, it's not 'done' by any stretch of the imagination and still requires enormous investment if it is to provide realistic amounts of power in the near term.

Re: this article - if they can use it to extract Uranium, then they can use the same technique to extract Thorium (or any other metal), which is much more plentiful anyway.

23rd August, 2012 @ 03:04 pm PDT

@StWils: I think you mean Bikini Atoll, which is in the Pacific Ocean. Bimini is off the cast of Florida.

Uranium reactors were originally favoured because one of the by-products was Plutonium, which was required to build up the vast stockpiles of nuclear weapons during the Cold War.

One wonders what quantity of sea water has to be filtered to make a measurable amount of Uranium.

23rd August, 2012 @ 04:58 pm PDT

So what TankThinker is saying is there aren't as many fools out there as we think.

I'm no expert, not even in the loosest sense of the word. Certainly less so than TankThinker.

Dr. Weinberg who held the patent on Nuclear Reactor technologies being used tried to persuade us to go the safer route which in today's technology means something like the LFTR. His reactor ran at Oak Ridge for perhaps 5-6 years, being shut down each Friday and started on Mondays.

Thorium is abundant, we know that. Why not invest more time and effort into proving the Liquid Fluoride Thorium Reactor, one way or another?

There are many knowledgeable people out there who think it is a good option. I appreciate TankThinker's input but would like to know what other options are being researched?

Dr. Veritas
23rd August, 2012 @ 05:07 pm PDT

re; StWils

Most of the radiation released at Chernobyl was in the form of radio carbon from the burning of graphite neutron moderator. This is a short half-life high energy gamma emitter. It is already gone. The excluded area around Chernobyl is now a de facto wildlife sanctuary.


re; TankThinker

The actual engineering cost-effectiveness of nuclear power is quite high, and would be higher if reactor cores were built on an assembly line, quality control would be easier as well but for there to be an assembly line set up it has to be accepted that the reactors will be purchased.

The cost of uranium is directly related to how fast it is being used so if uranium eating nuclear reactors are built the price of uranium will go up making extracting uranium from seawater cost-effective (Basic economics). Also the cost of the uranium is only a tiny percentage of the cost of uranium fueled nuclear power generation the monetary price of uranium fueled nuclear generated electricity, and ship propulsion would not be noticeable being hidden by general inflation. If a country decides to go with nuclear power and simply mocks and ignores the anti-technology fascists The reactors could start coming online withing 5 years and make electricity for the nonindustrial consumer too cheep to meter.

As for disposing of conventional (uranium fueled {this includes plutonium fueled reactors}) nuclear waste.

Thorium as a nuclear fuel needs a boost to generate useful output this is real convenient because the waste from conventional reactors works real well for this and the reaction transmutes the conventional reactor waste and the thorium fuel to effectively harmless materials.

Cheap nuclear power would also put coal out of business stopping the widespread release of radioactive material found in the coal.

World wide cheep electricity would raise every bodies standard of living most importantly the third worlds lifting the poor out of soul crushing poverty to the point that they can see the advantage of taking care of the environment making the world cleaner and greener.

The poor will always be with us but that does not mean that there has to be starving, uneducated, children digging through trash looking for something that is vaguely edible. If we use it nuclear power will help us end that obscenity.

23rd August, 2012 @ 05:15 pm PDT

re; Synchro

In the general yes but the chemistry has to be specific to that which you wish to extract.

The same techniques that the Israelis use extracting industrial chemicals out of the Dead Sea can be used on the water from any ocean.

23rd August, 2012 @ 06:03 pm PDT

They say we will run out of Uranium in 50 years, just like we ran out of fossil fuel (as they predicted in the 80's).

Oh. Wait a sec. There seems to be some left still?

23rd August, 2012 @ 07:33 pm PDT

uranium is one of the sources for helium which is going to be in much more demand than nuclear power or bombs. Given that the deuterium in the ocean is as prevalent as it is- what about cold fusion as a source of helium?

I ask because with one of the major helium refiners doing 3 weeks of routine maintenance at a uranium mine the spot pricing has gone thru the roof ($100/L to $2000/L )and supplies are almost nonexistant.

24th August, 2012 @ 06:07 am PDT

re; Kwazai

If you want to get helium through atomic transmutation you are better off bombarding lithium with neutrons and collect the tritium (hydrogen 3) and then use a fuel cell and combine the tritium with oxygen producing heavy-heavy-water which is easy to contain while the tritium decays into helium 3. You can use the lithium as a liquid metal coolant in a nuclear reactor to do the bombarding.

25th August, 2012 @ 12:26 am PDT

I don't know for sure but don't believe the uranium is evenly dispersed throughout the ocean but rather concentrated in heavy salt brine flows along with other valuable minerals that would help spread out costs over several income sources. Currently, there is work being done to extract lithium from seawater than mining it. Additionally, a concentrated solar power station can help to offset costs further by making concentrated brine, providing direct heat for processing, and electricity.

Gary Richardson
1st September, 2012 @ 09:25 pm PDT

Perhaps this technology could be tweaked to also filter mercury, PCB, and dioxin pollution from the ocean water in areas where fish that we eat are known to live or migrate.

I wonder if the uranium collecting efficiency of the technology could be drastically enhanced by strategically placing the filter where a large storm just passed, or where a large submarine earth quake just occurred. Perhaps those events are energetic enough to naturally stir up ocean sediment that I assume may be rich in rare earth minerals. Or maybe the filters could be placed near hyrothermal vents. Those things seem to spew out all kinds of geo-goodies.

2nd September, 2012 @ 03:08 pm PDT

Is anybody working on a similar extraction method for radioactive isotopes (like those spilled at Fukushima) from sea water or at least after desalinating water if that helps concentrate it economically?

29th December, 2013 @ 04:05 am PST
Post a Comment

Login with your gizmag account:

Or Login with Facebook:

Related Articles

Just enter your friends and your email address into the form below

For multiple addresses, separate each with a comma

Privacy is safe with us because we have a strict privacy policy.

Looking for something? Search our 26,451 articles