The volume of the world's oceans is so huge that seawater can almost provide limitless amounts of uranium - some around 4.5 billion tons, even though one ton seawater contains only about 3.3 mg Uranium. Therefore, developing effective adsorbents for uranium extraction from seawater is very promising. So far, the most efficient adsorbents are solid polymers containing amidoxime groups (-(NH2)=N-OH), which show high affinity and selectivity for uranyl ion, i.e. approximately ten fold greater than the conventional titanium oxide adsorbent. However, these polymeric adsorbents usually have lower Brunauer-Emmett-Teller (BET) surface area and low mechanical strength. To increase the surface area of the polymeric adsorbent, we copolymerized the amidoxime generating monomers on the surface of high surface area mesoporous carbon. With increasing the ratio of monomers/carbon, the uranyl ion adsorption capacity increases whereas the BET surface area decreases correspondingly. The capacities of uranyl ion adsorption from the best sample are 19.1 g U/kg and 63.3 g U/kg, respectively, for 50 mL and 250 mL uranium stock solutions. The results are higher than the Japanese sample under the same conditions (18.2 g U/kg and 35.4 g U/kg for 50 mL and 250 mL uranium stock solutions, respectively), indicating our sample has higher selectivity for Uranium. The real sea water test on the best polymer coated carbon composite adsorbent is under investigation.

Isolating trace seawater uranium with polymer functionalized porous carbon

244th National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.