Search for significant resources in seawater

Tamada, Masao

The Black Current conveys 5.2 million tons of uranium toward the offing of Japan, though uranium concentration is only 3.3 ppb in seawater. Recovery of 0.2% of this resources can supply the uranium for all atomic power plants in Japan. Graft polymerization is a promising technique to prepare adsorbent having high selectivity to uranium in seawater and enough durability in severe sea conditions. To evaluate the activity of the adsorbents the equipment for the recovery of rare metals from seawater was set at the 7 km offing of Mutsu-Sekine, Aomori prefecture on September, 1999. In three years (1999 - 2001) 9 mooring experiments of adsorbents were carried out and 1 kg uranium as yellow cake was recovered. This experiment suggested that hydrophilic monomer and trunk polymer should be improved to realized the higher activity for uranium recovery from seawater.