Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Environment

Mining The Sea: Scientists Refine Methods For Extracting Uranium From The Ocean

by Stephen K. Ritter
April 6, 2015 | A version of this story appeared in Volume 93, Issue 14

 

U Grab
[+]Enlarge
Credit: Ind. Eng. Chem. Res.
Polymers containing amidoxime groups trap UO22+ ions with a tridentate grip; C is gray, O is red, N is blue, H is white, and U is the large silver atom.
A polymer containing amidoxime groups trap UO22+ ions; U is silver, C is gray, O is red, N is blue, and H is white.
Credit: Ind. Eng. Chem. Res.
Polymers containing amidoxime groups trap UO22+ ions with a tridentate grip; C is gray, O is red, N is blue, H is white, and U is the large silver atom.

The world’s oceans contain a near-limitless source of untapped uranium for nuclear power production—some 4.5 billion tons, or nearly 1,000 times as much as land resources, according to Christina Leggett of Lawrence Berkeley National Laboratory. Leggett was a speaker at a two-day Division of Industrial & Engineering Chemistry symposium on extracting uranium from seawater at the American Chemical Society national meeting in Denver last month.

More on this story

Mining The Sea: Scientists Refine Methods For Extracting Uranium From The Ocean

In Denver, the symposium speakers largely focused on new developments in preparing adsorbent materials for economically viable and environmentally friendly uranium harvesting. These materials are simply dropped into the ocean where they soak up uranium. The sorbents are periodically plucked from the water, stripped of uranium, and plunged back in.

Uranium extraction is complicated, Leggett explained, because under the slightly alkaline conditions of seawater uranium exists as the very stable and inert Ca2[UO2(CO3)3] complex. Leggett and her coworkers are investigating poly(acrylamidoxime) sorbents in which the amidoxime groups, –C(NH2)NOH, are selective for UO22+ ions. The technique could also be expanded to fish out other valuable metals from the sea.

But the sorbent technology is still too inefficient and too expensive to compete with mining on land. The researchers are looking at alternative polymers and functional groups as well as coming up with new braided textile designs that could improve sorbent capacity and durability.

The effort is not just about finding any solution, said Robin D. Rogers of McGill University, in Montreal, who co organized the symposium. “This is an effort to develop a green extraction process to get around existing processes that can be quite dirty, and to do it economically.”

Advertisement

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.