Extracting Uranium from Seawater for Nuclear Fuel

Oceans, covering a substantial portion of Earth’s surface and hosting a diverse range of life, also contain a dispersed population of uranium ions. Extracting these ions from seawater could provide a sustainable fuel source for nuclear power generation.

Scientists, as reported in ACS Central Science, have developed a material for electrochemical extraction that efficiently attracts elusive uranium ions from seawater, outperforming existing methods. Nuclear power reactors harness the energy stored within atoms through fission, breaking apart uranium atoms due to their inherent instability and radioactivity.

Uranium

Currently, uranium is primarily extracted from rocks, but the availability of uranium ore deposits is limited. The Nuclear Energy Agency estimates that the oceans contain over 4.5 billion tons of uranium in dissolved uranyl ions, surpassing the land reserves by over 1,000 times.

However, extracting these ions presents challenges due to the insufficient surface area of existing materials for effective ion trapping. In response, Rui Zhao, Guangshan Zhu, and their team aimed to create an electrode material with a highly porous structure suitable for electrochemically capturing uranium ions from seawater.

The researchers initiated the process with a flexible cloth crafted from carbon fibers to produce the electrodes. The cloth underwent coating with two specialized monomers, followed by polymerization. Subsequently, the cloth was treated with hydroxylamine hydrochloride to introduce amidoxime groups to the polymers.

The inherent porous structure of the cloth resulted in numerous small pockets where amidoxime could settle, facilitating the effective trapping of uranyl ions. In experimental setups, the team deployed the coated cloth as a cathode in seawater, whether naturally sourced or enriched with uranium, added a graphite anode, and ran a cyclic current between the electrodes.

Extracting uranium from seawater for nuclear fuel: Tests using seawater from the Bohai Sea

Over time, the cathode cloth accumulated bright yellow, uranium-based precipitates. In tests using seawater from the Bohai Sea, the electrodes extracted 12.6 milligrams of uranium per gram of water over 24 days. The capacity of the coated material surpassed that of most other uranium-extracting materials tested by the team.

Moreover, employing electrochemistry to trap the ions proved to be approximately three times faster than allowing them to accumulate naturally on the cloths. The researchers assert that this study presents an efficient approach to extracting uranium from seawater, potentially establishing oceans as new nuclear fuel sources.

Therefore, the authors express gratitude for the funding received from various sources, including the National Key R&D Program of China, the National Natural Science Foundation of China, the Project of Education Department of Jilin Province, the Natural Science Foundation of the Department of Science and Technology of Jilin Province, the Fundamental Research Funds for the Central Universities, and the “111” project.

Read the original article on ScienceDaily.

Read more: KSTAR’s Latest Upgrade: Potential Breakthrough in Nuclear Fusion.