A research team from MIT may have figured out a way to clean up a large amount of nuclear wastewater from the Fukushima disaster. They have developed a way to use shock electrodialysis to decontaminate the water.
Originally the team invented the shock electrodialysis to remove salt from seawater. The process creates a shockwave, which pushes electrically charged particles or ions to one side of a tube that’s filled with a charged porous material. This allows a stream of concentrated contaminants to be filtered out from the rest of the water.
Nuclear power plants use large amounts of water necessary for cooling purposes. One of the problems this creates is the water becomes highly contaminated with radioactive isotopes, and these require a special long-term disposal process.
The MIT scientists discovered that two radionuclide contaminants, isotopes of cesium and cobalt, can be selectively removed from the water, which also contains lithium and boric acid. Once the water is cleansed of the cesium and cobalt, the water can be recycled through the cooling system and reused in the reactor. This could amount to 10 million cubic meters of water per year that can be reused by a large reactor.
The research team was led by Professor of Chemical Engineering Martin Bazant. Who says, “It’s a single device that can perform a whole range of separations for any specific application. We carefully measure the composition of all the stuff going in and out.”
Bazant and the team’s system is inexpensive and scalable to large sizes, along with being able to handle a large range of contaminants. For their tests, the team used a recipe provided by Mitsubishi Heavy Industries to simulate nuclear wastewater. In a three-stage separation process, they were able to remove 99.5% of the cobalt radionuclides from the water. From this, they were able to retain and reuse around 43% of the treated water. They also discovered that the water is still reusable if it’s cleaned with 98.3% of the contaminants being removed.
As the research went along, the team started to focus on separation processes that would be useful for health reasons. While this method has many potential applications, Bazant said that “nuclear wastewater is one of the first things the team thinks they can solve, for which no other solution currently exists.”
For their ongoing research, they will look to develop a system to remove lead from drinking water, along with other contaminants.
For now, it would be a huge success for everyone if this operation can be scaled up to help clean up the water containers that hold millions of gallons of contaminated [water] from the Fukushima disaster. Bazant said he’s hopeful that large-scale decontamination will be possible “within a few years.”
Nuclear waste challenges extend well beyond contaminated water. Spent reactor fuel, with its multi-hundred-thousand-year hazard profile, has been a harder problem to crack. In 2025, however, researchers at Canadian Nuclear Laboratories demonstrated that a single chemical process can extract 89% of long-lived transuranic material from real spent fuel in 24 hours, turning a persistent disposal liability into potential reactor fuel.
