TOKYO — Japanese researchers have found more than 16 million tons of rare-earth deposits, equivalent to a few hundred years of global consumption, under the seabed near the island of Minami-Torishima, about 1,900km southeast of Tokyo.
The research team, led by Yutaro Takaya, an instructor at Waseda University, and Professor Yasuhiro Kato of the University of Tokyo, published detailed findings on the size of the deposits for the first time on Tuesday in Scientific Reports, a U.K. online scientific journal. They also said they had come up with the technology to allow the resources to be extracted efficiently. The researchers plan to work with private companies to recover the rare earths.
Rare earths are used in a range of high-tech products, including hybrid and electric cars, as well as magnets for wind turbines and florescent materials for light-emitting diodes.
Much of the world relies heavily on China for rare earths, a concern for some. China accounts for about 90% of global production and its dominant position has resulted in price spikes and shortages in the past.
The newly found resources lie within Japan’s exclusive economic zone, and recovering them could help the country lose its standing as a resource-poor country.
The research team collected samples of the rare earth elements in 25 locations on the seabed across a 2,500 square-kilometer area south of Minami-Torishima and analyzed their density.
The analysis found 730 years’ worth of global demand for dysprosium, used for the magnets in hybrid cars, and 780 years’ worth of yttrium, used in lasers.
The recovery method developed by the team was based on work with calcium phosphate, a composite substance in teeth and bones.
The substance contains a high density of rare-earth elements and has a large particle diameter. The team conducted experiments to separate it using centrifugal force and found that the density can be raised by up to 2.6 times. The method can boost the density of rare-earth elements to 20 times that of deposits in mainland China.
“The realization of rare-earth resources development has come into sight because of the sharp increase in economic efficiency [of recovery],” Kato said.
In 2012, Kato’s team discovered an area near Minami-Torishima that appeared to contain a large deposit of rare-earth elements. They formed a consortium to develop the technology to extract the resources that included Modec, a Japanese builder of offshore floating platforms, and Toyota Motor.