A team of researchers at Kindai University and other collaborators has succeeded in removing the radioactive substance tritium from water, raising hopes of fully decontaminating the tainted water stored at the Fukushima No. 1 nuclear power plant.

Tritiated water is said to be difficult to separate from ordinary water as the two substances have similar chemical properties.

Tatsuhiko Ihara, a professor in the Faculty of Engineering at Kindai’s Hiroshima campus, and others used processed aluminum powder to develop a filter that has numerous superfine pores with diameters of 5 nanometers or less, the university announced Wednesday. One nanometer is equal to 1 billionth of a meter.

After putting water contaminated with radioactive materials, including tritium, through the filter, only tritiated water was caught in the pores, making it possible to separate the substance in a highly efficient manner, according to the team.

The tritiated water can then be removed from the filter by heating it so the device can be reused, thus keeping costs down.

“We want to reduce the amount of contaminated water at the Fukushima No. 1 nuclear power plant,” Ihara said.

The plant is set to be decommissioned over the next several decades, as three of its six reactors suffered nuclear meltdowns after being struck by tsunami triggered by the massive March 2011 earthquake.

Water contaminated with radioactive materials in the process of cooling the damaged reactors is building up in the storage tanks at the site as tritium, a radioactive isotope of hydrogen, cannot be removed using the existing water processing facility there.

Regulatory authorities have called for the processed water to be drained into the sea, but locals, especially fishermen, are opposed to the idea as the water still contains tritium.

The research team includes representatives of Kindai’s Faculty of Engineering, the university’s Atomic Energy Research Institute, Toyo Aluminium K.K. and A-Atom Technol Co., a startup that measures and analyzes radiation. The team has applied for an international patent on the technology.