This photo shows the equipment capable of separating tritium water. (Photo courtesy of Kindai University)

OSAKA -- A team of researchers from Kindai University and private companies in western Japan has developed a new filter enabling the removal of water containing radioactive tritium.

The researchers hope their technology will eventually be used in processing water leaking from the Tokyo Electric Power Co.'s crippled Fukushima No. 1 Nuclear Power Plant. The waste water contains tritium but the radioactive material cannot be removed with the current filtering technology.

Tritium is an isotope of hydrogen. Water containing tritium has chemical features almost identical to water with ordinary hydrogen, and separating tritium water is difficult.

The research team, comprising professor Tatsuhiko Ihara of Kindai University specializing in inorganic material chemistry, and researchers from Osaka-based Toyo Aluminium K.K. and others, has developed an aluminum filter with extremely tiny holes 5 nanometers or less in diameter each. The filter can stop vapors of tritium water, and the separation rate was "almost 100 percent," according to a team representative.

At the Fukushima No. 1 plant, over 800,000 metric tons of radioactive water that leaked from the facility is stored on the premises. The research team will cooperate with local companies in Fukushima Prefecture and others to develop equipment that can be put to actual use to separate tritium.

The radioactive material exists in the natural environment, and the Nuclear Regulation Authority maintains that there should be no problem in releasing water containing tritium into the sea if its concentration levels are lowered sufficiently. This stance faces strong oppositions from local fishermen and others who worry about negative rumors about their catches due to the discharge of such water. The government has set up a panel of experts to examine how to process tritium water.

(Japanese original by Koki Matsumoto, Osaka Science & Environment News Department)