Uranium From Seawater Advances

This is a couple of years back, but I’d not noticed it until now. It’s still kind of a ‘big thing’.

The Japanese had developed a method to extract U from seawater using plastic mats with specially formed attachment points for metal ions on the surface. These folks enhance it (on a cost basis) by making the surface very much finer. The Japanese idea was to anchor these deep of the coast where it is dark enough that algae do not grow and in the Japan current so there is no pumping cost, then pull them up a year later and take the U out. The cost, IIRC, was about $140 / unit when U from land was selling for about $120, so not an economical competitor, but would still make electricity vastly cheaper than wind turbines or solar (or even oil and gas).

Since then, U has had a price collapse and a bit of a recovery, but I’m not sure where we are at the moment. In any case, this tech assures that we can have all the U needed to run the planet forever. Why? Because more new U washes into the ocean each year as mountains erode, and the quantity going in is greater than we would need to take out to run everything.

https://chiefio.wordpress.com/2009/05/29/ulum-ultra-large-uranium-miner-ship/

has my idea for an alternative to sea bed placement. One that would work even for landlocked countries. But on to the article.

http://www.sciencedaily.com/releases/2012/08/120821212634.htm

Moving closer to extracting uranium from seawater

Date: August 21, 2012
Source: DOE/Oak Ridge National Laboratory
Summary: Fueling nuclear reactors with uranium harvested from the ocean could become more feasible because of a new material.

I would point out that it is already “feasible”, just a cheaper source exists in the mined deposits on land. A modest price rise and this becomes the winner without any change of technology.

Fueling nuclear reactors with uranium harvested from the ocean could become more feasible because of a material developed by a team led by the Department of Energy’s Oak Ridge National Laboratory.

The combination of ORNL’s high-capacity reusable adsorbents and a Florida company’s high-surface-area polyethylene fibers creates a material that can rapidly, selectively and economically extract valuable and precious dissolved metals from water. The material, HiCap, vastly outperforms today’s best adsorbents, which perform surface retention of solid or gas molecules, atoms or ions. HiCap also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory.

Note that they can customize just which metals get removed from the water and it specifically lists “precious dissolved metals”. I have to wonder if that means gold too.

“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 ORNL’s Materials Science and Technology Division.

Results were presented August 21 at the fall meeting of the American Chemical Society in Philadelphia.

HiCap effectively narrows the fiscal gap between what exists today and what is needed to economically extract some of the ocean’s estimated 4.5 billion tons of uranium. Although dissolved uranium exists in concentrations of just 3.2 parts per billion, the sheer volume means there would be enough to fuel the world’s nuclear reactors for centuries.

As noted above, it isn’t just centuries. We run out of Uranium when we run out of planet, or erosion of mountains stops. I.e. millions of years minimum.

The goal of extracting uranium from the oceans began with research and development projects in the 1960s, with Japan conducting the majority of the work. Other countries pursuing this dream include Russia, China, Germany, Great Britain, India, South Korea, Turkey and the United States. Many adsorbent materials have been developed and evaluated, but none has emerged as being economically viable.

What sets the ORNL material apart is that the adsorbents are made from small diameter, round or non-round fibers with high surface areas and excellent mechanical properties. By tailoring the diameter and shape of the fibers, researchers can significantly increase surface area and adsorption capacity. This and ORNL’s patent pending technology to manufacture the adsorbent fibers results in a material able to selectively recover metals more quickly and with increased adsorption capacity, thereby dramatically increasing efficiency.

“Our HiCap adsorbents are made by subjecting high-surface area polyethylene fibers to ionizing radiation, then reacting these pre-irradiated fibers with chemical compounds that have a high affinity for selected metals,” Janke said.

After the processing, scientists can place HiCap adsorbents in water containing the targeted material, which is quickly and preferentially trapped. Scientists then remove the adsorbents from the water and the metals are readily extracted using a simple acid elution method. The adsorbent can then be regenerated and reused after being conditioned with potassium hydroxide.

In a direct comparison to the current state-of-the-art adsorbent, HiCap provides significantly higher uranium adsorption capacity, faster uptake and higher selectivity, according to test results. Specifically, HiCap’s adsorption capacity is seven times higher (146 vs. 22 grams of uranium per kilogram of adsorbent) in spiked solutions containing 6 parts per million of uranium at 20 degrees Celsius. In seawater, HiCap’s adsorption capacity of 3.94 grams of uranium per kilogram of adsorbent was more than five times higher than the world’s best at 0.74 grams of uranium per kilogram of adsorbent. The numbers for selectivity showed HiCap to be seven times higher.

So you might expect this to be close to commercially viable already, given the prior art being “close”. But prices change…

A little newer at 2013, and from MIT, we have another approach:

http://www.technologyreview.com/news/514751/novel-material-shows-promise-for-extracting-uranium-from-seawater/

Novel Material Shows Promise for Extracting Uranium from Seawater

A so-called metal-organic framework could offer a better way to get at the vast uranium resource dissolved in the ocean.

By Mike Orcutt on May 16, 2013

A new material could potentially be used to extract uranium from seawater more efficiently, new research suggests.

[…]
The most advanced system today employs plastic fibers with uranium-binding chemical groups grafted onto their surface. Now, researchers led by Wenbin Lin, a professor of chemistry at the University of North Carolina at Chapel Hill, have designed a metal-organic framework (MOF) to collect common uranium-containing ions dissolved in seawater. In lab tests, the material was at least four times better than the conventional plastic adsorbent at drawing the potential nuclear fuel from artificial seawater.

At this point I have to wonder if “conventional” is the older Japanese material or the newer but still pre-2013 ORNL material. If the former, this has a way to go, if the latter, we have another step forward. I think, though, that it is the older Japanese benchmark.

Metal-organic frameworks are considered very promising for certain technological applications, including gas storage and chemical separation. Their structure can be tuned for different purposes. This allows them to be made extremely porous, resulting in very high surface areas—an order of magnitude larger than that of zeolites, a porous material already used in many commercial adsorbents. And like organic polymers, metal-organic frameworks have surfaces that can be modified so as to bind to specific molecules.

One reason it’s challenging to draw uranium-containing ions from seawater efficiently is that they occur at an extremely low concentration of three parts per billion. The established method, which has been demonstrated at a fairly large scale, entails dropping large amounts of plastic adsorbent into the ocean and leaving it for several weeks before retrieving it and removing the uranium haul. But the ocean contains many other ions that can bind to the adsorbent and block uranium from attaching.

The most advanced materials, which can be reused several times, can draw between three and four milligrams of uranium per gram of plastic each time they’re used, says Costas Tsouris, a researcher at Oak Ridge National Laboratory who is working on that system.

In the lab, with no competition from other ions, Lin’s material collected over 200 milligrams of uranium per gram of adsorbent. This affinity for uranium, says Lin, is due to the precise design of the material’s three-dimensional structure. Organic chemical groups that grab onto uranium are arranged within the pores of the metal-organic framework to form “binding pockets,” he says. The research was published last month in the Royal Chemical Society’s journal Chemical Science.

So the HiCap stuff up above was 146 in test liquid, 3.94 in seawater. Compared to the statement just above with “three to four” and it sounds like they are using that HiCap system as their comparison base (and the ORNL guy working on it is a clue too). But they are just 200 in ‘the lab’. So it’s a 200 vs a 146 both in test liquids, which is a nice kick up, but not dramatic. Nice to have two good systems though, in case one “has issues” in actual use.

Tsouris calls the results “very encouraging” but cautions that it remains to be seen how the material will perform in more realistic conditions. In real seawater, where other ions would be competing to attach, the material would probably not perform as well as in the lab demonstration, says Erich Schneider, a professor of nuclear and radiation engineering at the University of Texas at Austin, who was also not involved in the new research.
[…]
Uranium obtained using the traditional process today would cost between $1,000 and $2,000 per kilogram—about 10 to 20 times the current market price, says Schneider. (The price of uranium did rise to around $300 per kilogram as recently as 2007, however.) The new process could cut that cost significantly.

Lin thinks it may eventually be possible to develop a metal-organic framework that is at least several times better than today’s system. He is confident that his lab can exploit the “tunability” of these hybrid materials to improve their affinity for uranium-containing ions and to address weaknesses that further testing may expose.

I find that $1000 to $2000 not credible. Yes, there has been some inflation time between the original Japanese results and now, but not that much. I suspect this is an inflated number so their product looks better on a cost basis.

http://phys.org/news/2013-11-sorbents-efficiently-uranium-seawater.html

This is from ORNL again, but from late 2013.

In the journal Angewandte Chemie, American researchers have now introduced a process by which they can produce tailored, highly effective adsorption agents to do this job.

Because the concentration of uranyl ions in seawater is very low, adsorption agents used for this process must be particularly efficient. By carefully controlling the surface and pore structures, a team from Oak Ridge National Laboratory and the University of Tennessee has now been able to significantly increase both the rate and capacity of adsorption of a new polymer adsorbent.

Their success stems from a special polymerization technique. Sheng Dai’s team begins by producing a porous polymer framework based on the monomer vinylbenzyl chloride (VBC) with divinylbenzene (DVB) as a cross-linking agent. It is possible to vary the surface properties and pore volume of the product by changing the ratio of VBC to DVB. The interiors of the resulting frameworks contain many accessible chloride species that then serve as starting points for the next polymerization step, which is known as atom-transfer radical polymerization (ATRP). This reaction allows the researchers to grow polyacrylonitrile chains within the framework. The advantage of ATRP is that the length of the chains is highly controllable and uniform. In the final step, the polyacrylonitrile is converted to polyamidoxime because amidoxime groups bind well to uranyl ions.
[…]
“These frameworks are the first example of ATRP initiators in which the initiator species is located within the nanoporous support network,” reports Dai. “This new process puts materials with tailored adsorption and surface properties within reach. The method can be used to produce a wide variety of polymer nanocomposites for applications including the removal of heavy-metal ions from solutions or novel catalysts.”

And again it looks like it generalizes to many metals.

http://www.sciencecodex.com/science_china_chemistry_special_topic_extraction_of_uranium_from_seawater-122383

Looks like China is getting in on the act… with an obligatory genuflect to Global Warming, sigh.

Extraction of uranium from seawater

posted by news on november 5, 2013 – 2:30pm

SCIENCE CHINA Chemistry published a special topic on extraction of uranium from Seawater recently.

Owing to the fast economic growing and the concern over greenhouse gases and air pollution, the development of nuclear energy is one important option to meet the expanded energy consumption in our future.

To achieve that goal, continuing and reliable supplies of uranium are critical to future nuclear power projects. As is well known, global terrestrial reserves of uranium are limited and the deposits in China are relatively small.
[…]
Japan is playing a leading role in the research of uranium extraction from seawater; it has collected more than one kilogram of uranium from seawater by immersing functionalized polyethylene fibers in ocean. The United States Department of Energy (DOE) supported a program in 2010 to start a project for uranium extraction from seawater, some universities and institutions have been engaged in such project.

Almost at the same time, a project was supported by the Chinese Academy of Sciences (CAS), although in a small budget, to evaluate the feasibility of extracting uranium from seawater and salt lake. This could be considered as a new era for the research on uranium extraction from seawater in China. CAS and DOE have now established a tight collaboration mechanism for uranium extraction from seawater.
[…]
In March 25-26, 2013, the workshop on extraction of uranium from seawater was held in Shanghai, with more than eighty attendees from China and five delegates from the US. This workshop was initiated by Prof. Zhifang Chai at Institute of High Energy Physics of CAS, and financially supported by the National Natural Science Foundation of China, Shanghai Institute of Applied Physics (CAS), and China Academy of Engineering Physics. There were four invited talks and twelve oral presentations. The numbers of attendees and presentations are much higher than expected. The topics presented at the workshop cover a wide range of areas, including computer modeling, synthesis of nanoparticle with large surface area, radiation induced grafting of polymer fiber and following amidoximation, sorption and elution processes, marine test, etc.

I would note that the concentration being increased, and maybe even a bit of filtering to prevent pore clogging junk might help. So why not put these plastic mats in the outflow pipes of desalinization plants where some filtration has already happened, the pumping is already being done, and the reject brine is already concentrated? Just sayin’…

http://www.newscientist.com/article/dn22201-record-haul-of-uranium-harvested-from-seawater.html

This one talks about the ORNL method in 2012, and has cost data that looks more realistic to me.

Record haul of uranium harvested from seawater

12:20 22 August 2012 by Will Ferguson
[…]

Cheaper method

To make this process more economical, ORNL chemical scientist Sheng Dai says US researchers used plastic fibres with 10 times more surface area than the Japanese design, allowing for a greater degree of absorption on a similar platform.

They tested their new design at the PNNL’s marine testing facility in Washington State. The results show the new design cuts the production costs of a kilogram of uranium extracted from seawater from $1232 to $660.

While extracting uranium from seawater is still five times more expensive than mining uranium from the Earth, the research shows that seawater uranium harvesting could be a much-needed economic backstop for the nuclear industry moving forward into the 21st century.

Now just a bit ago we saw a quote of U at $300 / kg in 2007, so this is only about 2 x that price. Very acceptable, and likely with a couple of more doublings of efficiency to go. Yet the current “spot” price is about $100 / kg. And these folks have a chart of historical prices that looks “icky” as there is the typical “spike and drop” of a bubble, and a long non-recovery tail.

http://www.indexmundi.com/commodities/?commodity=uranium&months=120

So it looks to me like this process is “good to go” with modest price rises to just a bit above historical norms / averages, but the price of U is just so volatile that at any given time it can be making money or be way too expensive. With land source U able to be shut in during down periods, and ramped up in good times; and with power reactors presently not being built in much of the world while the old fleet ages out; even with a bit of added tech, it will be an economically tough market to sell into.

In short we need to see about another 5x to 10x improvement in cost performance, or price rise of land source U, before this displaces mines on land and takes over. Likely possible, but not soon. Also more likely to happen in China with low cost structures and little U to mine on land (and the ability of the government to do things for strategic goals anyway).

Yet things march on…

http://phys.org/news/2014-10-uranium-extracting-technology-seawater-award-grad.html

Notes that a grad student got an award for his PhD. Thesis on those metal organic cages seen above at U.Chicago.

Uranium-extracting technology for seawater earns research award for grad student
Oct 30, 2014
[…]
Abney, Lin, and two co-authors presented the first application of MOFs as a means of extracting uranium from seawater in the April 2013 issue of Chemical Science. Abney’s contribution to that work has since earned a First Prize in the 2014 U.S. Department of Energy’s Innovations in Fuel Cycle Research Awards Competition.
[…]

On the back end of nuclear power generation, materials prepared from MOF precursors can help remove minor actinides during waste processing. These are the highly radioactive elements other than uranium and plutonium that occur in relatively low concentrations. The radioactivity of the waste solution would be dramatically reduced and decay to safe levels more quickly if the minor actinides could be separated from the other elements in nuclear waste.
“You essentially consolidate the radioactivity into a condensed and stable form, which is more amenable to long term storage and disposal than liquid waste,” Abney said.

Which has me also wondering if this stuff could be tailored to selectively separate U from Th from Pa… but I digress…

Abney and his fellow team members noticed that enzymes and proteins can have an unusual affinity for specific molecules. They suspected that they could use the three-dimensional structure of the metal-organic frameworks to produce a binding pocket similar to those of the enzymes or proteins. They could then create a more efficient, lightweight version of a molecule that mimics the structure and function of the protein or enzyme.
MOFs are many times lighter than proteins, while capable of achieving similar local structure. A protein that absorbs one uranium atom extracts less than one-tenth of one percent of its final mass. A MOF cage offers similar three-dimensional connectivity as the protein, but weighs around 100 times less and may have multiple binding sites. The MOFs reported in this study absorbed slightly more than 20 percent of their mass in uranium.

Now that looks to me like the active part only, not including the entire mat mass, but still, 20% mass:mass is a nice ratio.

http://www.ce.gatech.edu/node/6434

It looks like Ga. Tech wants in the action and got a grant to try to improve the ORNL method

Yiacoumi, Tsouris Win Energy Dept. Funding to Improve Uranium Extraction from Seawater

August 21, 2014 – 16:52 — jstewart74

CEE researchers Sotira Yiacoumi and Costas Tsouris received funding Wednesday to help improve the extraction of uranium from seawater.

The grant comes from the U.S. Department of Energy as part of a group of awards for nuclear energy research and development projects. Yiacoumi and Tsouris are one of four Georgia Tech teams that received a piece of the $67 million in funding.

They proposed to optimize the performance of a new adsorbent developed by the Oak Ridge National Laboratory that soaks up uranium in the world’s oceans. The idea is to make such extraction more economically viable, something scientists have been working on for decades.

$67 Million. Must be nice… and not a drop for Climate Skeptics…

In Conclusion

We have a current in hand technology that is about 6 x the present market price of Uranium from land. It is only about 2 x the price of uranium from land during recent market periods, and likely can be improved at least that much with modest enhancements of technology or reductions in costs from things like economic production of large quantities and reduced costs for leaching from the mats.

But with the current market condition, low projected demand in coming years as old plants shut down and new are not built, I see nothing forcing prices back up to the peaks of the past any time soon.

So the “good news” is that things are moving forward to ever cheaper and more effective extraction methods for ocean Uranium. And that the present “cost to produce” is well inside the range at which you can still make a bundle on the electricity produced.

https://www.physicsforums.com/threads/uranium-energy-equivalence.271720/

1 kg of fuel is equivalent to 1000-2000 tons of coal depending on how you measure it.
[…]
Indeed. Actually, I’d say, that’s the really fissioned fuel. To run a 1 GW electric plant, with a 33% steam cycle efficiency, you need about 2 800 000 TOE (tons of oil equivalent). Now, taking that per unit of mass, coal is slightly better than oil, we arrive at somewhat more than 2 million tons of coal per year. Currently, the burnup of fuel in a PWR is around 50 GW-day per ton thermal, and if we take the same steam cycle efficiency, this brings us around 20 tons of enriched uranium that is used up. But actually, only 5% is fissioned (about 3.3% from the original U-235, and about 1.7% from the bred plutonium), so only 1 ton is actually fissioned. To make those 20 tons of enriched uranium, one has usually started with 10 times as much, 200 tons. (one can do better, but then this needs higher separation work). So we have: 1 GW electric for a year = more than 2 million tons of coal 200 tons of natural uranium / 20 tons of enriched uranium / 1 ton actually split in a PWR In a fast breeder, ideally, 1 ton of natural uranium would be entirely split so ideally, 1 ton of natural uranium would also yield 1 GW electric for a year.

So depending on how you measure, and if you use it enriched in a ‘one and done’ or whole in a fast breeder, you get between 10 ton of coal and 2000 tons of coal.

http://www.infomine.com/investment/metal-prices/coal/1-month/

Has present thermal coal at about $50/ton.

So that $660 kg of U is about the same fuel value as $500 or $50,000 of coal as a rough approximation and depending on your reactor type. So in terms of actual energy costs, the U as fuel is still dirt cheap. Just not as cheap as the U coming from real dirt…

Now this is still interesting, as it caps ultimate U costs and through that ultimate electricity costs (provided markets work instead of stupid government mandates and subsidies…) at about double the normal U cost or 6 times the present depressed cost, and well below the cost of coal (that is way cheaper than natural gas, oil, wind, solar, whatever). As research proceeds, that cap gets lower until at some point there is crossover and more expensive land sources get shut in as no longer competitive. IMHO, in about 2030 we’ll have economical sea water sourced U and a hard lid on mined U prices. China will do it first, and likely about 2025 as their labor, land, environmental, and regulatory costs will all be lower and as they will want a demonstrated “from the sea” source for strategic (and perhaps military) reasons.

Any sudden renewed build of nuclear facilities around the world (i.e. China) that drives up the spot market price of U to common recent values will only accelerate this process.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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4 Responses to Uranium From Seawater Advances

  1. E.M.Smith says:

    I probably ought to have put in this one that the existence of this technology, and the estimated cost structure even at this stage, clearly “puts the lie” to whole garbage notion of “peak Uranium”; but it was already pretty clearly garbage from the get go…

    Also as one group is working on a more space and cost efficient backbone / mat, and the other is pushing a more effective “grabber” end molecule, just mixing the two main tech improvements from above will result in another step forward. But it will be a while before the two competing methods get mixed (both for ego and for licensing purposes…). But once commercial licensing of the tech moves forward, the folks buying those licenses will mix them.

  2. Larry Ledwick says:

    And as you say any reasonably intelligent process engineer would suggest ways to concentrate the input stream.

    Say take the output brine from a large desert solar distillation plant, let it set in concentration ponds until the “all natural” sea salt precipitates out and take the residue brine and pass it through the ion extraction mat cells as a final step.

    A process which is not quite economically viable all by itself could easily be viable if you cascade several product harvests together in the same plant (ie fresh water, “all natural sea salt” pure sodium chloride, potassium chloride both useable in water softeners and the potassium salts for agriculture and high value trace metals like gold and uranium from the remaining brine stream.)

    In desert countries where fresh water is in short supply the market value of the water alone would pay most of the physical plant costs.

  3. E.M.Smith says:

    @Larry:

    Know of any desert countries with a need for fresh water, love of gold, short on agriculture so needing ag salts (and using solar greenhouses / solar stills for food) who might want some nuclear fuel? Yeah, me too ;-)

    Oh, and I likely ought to add that any country wanting “boom stuff” and with no indigenous U supply could easily set up one of these in a ship cruising around and get the U they want without being observed. The rest being processing… that in the other posting I’ve shown could likely be done in the same ship, modulo some gammas giving it away and a waste water tail…

    Though I would divide it into two parts. Ships getting the raw U and Th from the sea, and underground reactor / processing out of sensor range.

    Simply put, as the cost, even at $600 to $1000 / kg is not prohibitive ( with, say, 2 ton needed, that’s $1.2 Million to $2 Million… i.e. ‘cheap’ compared to the rest of the program) the availability of raw U and Th is just not an issue any more, and the ability to track activity “from the mine” pretty much gone too.

  4. DocMartyn says:

    Don’t use sea water, use the more saline outflow from a desalination plant.
    Then look at the metals you also get, Strontium $1 per gram, Rubidium at $60.80 per gram, Molybdenum $0.44 per gram, Vanadium $2.2 per gram and Scandium $270 per gram.
    It doesn’t matter if you are pulling down other metals as long as you can sell them at a profit.

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