view of nuclear power plant towers
March 17, 2016

New method makes nuclear waste much safer to store and transport

Scientists modified a technology created for solar energy to remove americium, one of the most complex and difficult-to-eliminate elements in nuclear waste pools, solving a decades-old problem in storing nuclear waste.

According to a study published in the journal Science, the research not only opens the door to scaling up one of the most efficient energy sources on the planet, but also adds a major element of completing the nuclear fuel cycle; a development, along with renewable energy, that could help power the world’s energy needs safely for the future.

"In order to solve the nuclear waste problem, you have to solve the americium problem," study author Tom Meyer, a chemistry professor at the University of North Carolina, said in a press release.

A long-term goal for nuclear energy

While Americium doesn’t have the same popularity as a plutonium and uranium, scientists have been attempting to take it out of nuclear waste for decades. Many research groups initially had success, only to be met with complications later on, making the solution unfeasible.

In the new study, researchers said they discovered a way to expunge the radioactive element without experiencing downstream difficulties that obstructed progress.

The technology developed in the new study is related to techniques used to in solar power to pull electrons from water molecules. In the americium project, researchers modified the technology to pull electrons from americium, which requires twice the maximum amount of energy input as splitting water. By eliminating three electrons, the team made americium act like plutonium and uranium, which is easy to remove with existing technology.

Nuclear fuel is primarily packaged as small solid pellets packed into long, thin rods. To reprocess them, the spent fuel is first dissolved in acid and the plutonium and uranium is then seperated.  Americium can now be divided with plutonium and uranium or taken out in a second step.

“With a scaled up solution, not only will we no longer have to think about the dangers of storing radioactive waste long-term, but we will have a viable solution to close the nuclear fuel cycle and contribute to solving the world’s energy needs,” said co-author Chris Dares, a researcher at UNC. “That’s exciting.”

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