New Material Can Soak Up Uranium From Seawater (acs.org)

A new adsorbent material "soaks up uranium from seawater, leaving interfering ions behind," reports the ACS's Chemical & Engineering News, in an article shared by webofslime: The world's oceans contain some 4 billion metric tons of dissolved uranium. That's roughly 1,000 times as much as all known terrestrial sources combined, and enough to fuel the global nuclear power industry for centuries. But the oceans are so vast, and uranium's concentration in seawater is so low -- roughly 3 ppb -- that extracting it remains a formidable challenge... Researchers have been looking for ways to extract uranium from seawater for more than 50 years...

Nearly 20 years ago, the Japan Atomic Energy Agency (JAEA) confirmed that amidoxime-functionalized polymers could soak up uranium reliably even under harsh marine conditions. But that type of adsorbent has not been implemented on a large scale because it has a higher affinity for vanadium than uranium. Separating the two ions raises production costs. Alexander S. Ivanov of Oak Ridge National Laboratory, together with colleagues there and at Lawrence Berkeley National Laboratory and other institutions, may have come up with a solution. Using computational methods, the team identified a highly selective triazine chelator known as H2BHT that resembles iron-sequestering compounds found in bacteria and fungi.... H2BHT exhibits little attraction for vanadium but has roughly the same affinity for uranyl ions as amidoxime-based adsorbents do.

Comments

So, if 1000x as much as we have...

[gweihir]

.. is enough for "centuries", then what we have should run out in less than a year? Seems somebody has trouble with numbers. While Uranium that can be mined is not nearly as plentiful as the nuclear-mafia wants you to believe, it should be enough for a few decades, given that no new reactors are constructed.

Re:So, if 1000x as much as we have...

[blindseer]

What you say is likely true, if we assume that there is a free trade of uranium. A nation with less than friendly relations with much of the world might have trouble getting uranium if their local geology is lacking in uranium. Access to the sea though means a constant supply of uranium at a very constant price. Extraction of uranium at any rate which we could conceive of is nothing compared to the size of the ocean, the concentration of uranium salts in the ocean will not be affected (on any human time frame).

As I recall nations such as India, Iran, and Japan don't have a lot of uranium that they can mine. At least not at the prices you gave. If this process gets to even double the market rate on what many pay now then it can still be viable because of costs due to transport and trade regulations.

There's also some possibility of another spike in uranium. I recall a co-worker being quite excited when he saw uranium prices spike. He was crushed later when he found out why. A mine he had invested in had been flooded with water, some weather event and/or mechanical problem at the site. This put a dent in future expectations of supply and that made uranium prices climb. If there's a technology on uranium extraction from seawater then we will see a ceiling on uranium prices as people build such facilities to back up their terrestrial mining. Oil people do this all the time, they drill for less than ideal oil because they need that well drilled before prices spike. If prices spike and there's no oil to sell then they can't cash in.

Investments in uranium from seawater would certainly happen if a government sees uranium supplies as a national security interest. Governments will invest in this even if the pay off later is little to nothing. Not having to beg others for energy gives a lot more security than investing in more battle tanks and bombers.

Re:So, if 1000x as much as we have...

[sfcat]

>given that no new reactors are constructed

Isn't that the point? There is no such thing as a truly "global nuclear power industry." To me, the 'centuries' estimate implies a global industry providing power to the entire world while also replacing fossil fuels and supporting a general increase of demand for energy as technology progresses.

Ok, so you want to do this in global total energy. So lets do that. World consumes about 50PWh of fuel (converting fuel to electricity for simplicity) and electricity a year. We get > 90% of that from fossil fuels right now. So about 8000h/yr (with a 90% capacity factor which is common in nuclear) and that's 6.25TWs of production or 6,250 1GW reactors. So a current generation LWR will consume about 200 tons every 4 years so that's 50 tons/yr/GW. So that's 312,500 tons per year or ~283,495 tonnes. So 4.5b tonnes mentioned above (which is renewed each year naturally at an unknown rate) would be about 15,800 years. Now, I've ignored the issue of enrichment, so let's adjust for that. So the fuel is about 3% enriched (2% for initial load, 4% for refueling rods) and that's 4x more U-235 than natural Uranium, so divide by 4.

So that's a hair under 4000 years of supply for all the worlds fuel and electricity at current rates. And as I said, its naturally replenished at an unknown rate. Its likely that if we used a lot of uranium from seawater that the increased difference in concentration would increase this rate of natural replenishment.

And of course, with Thorium we have far larger reserves than Uranium and since we burn up the common isotope of Thorium we end up with far more energy per amount of raw material and a 300 years supply of the stuff is sitting around in slag heaps across the world and that doesn't count all the huge piles of the stuff near every rare earth mine. So no, there is no way we are running out of nuclear fuel anytime soon. Try doing this with any other energy source and you either get climate change (fossil fuels) or you have to ramp up mining to an absurd degree to get the raw materials you need. Try doing some research into what it would take to get 100% of just CAs energy needs from renewables (hint nameplate capacity isn't what counts). You quickly run out of the entire world's supply of various types of raw materials (including land) for any scheme you ramp up. This is why nuclear is really the only good option we have or likely will have in our lifetimes.

"The man who ploughed the sea"/A.C. Clarke

[mykepredko]

It's amazing how many concepts and technologies have been predicted by early science fiction.

As soon as I saw the headline, I thought of Arthur C. Clarke's "The man who ploughed the sea" and how it is a cautionary tale for people who think about investing with fast talkers.