I can't quite tell how practical this could be since the article makes no mention of the exact cost nor how much quantity is needed per year per plant to absorb the radioactive ions, but here's the latest development:
AUSTRALIAN researchers say they have created a low-cost material to filter and safely store nuclear waste.Funny how the Australians came up with this idea and they don't even have a nuclear plant in their country!
The potential breakthrough for the environment was made by a team of scientists from Queensland University of Technology, led by Associate Professor Zhu Huai Yong from the School of Physical and Chemical Sciences.
Professor Zhu said the QUT team had discovered how to create nanofibres, which are millionths of a millimetre in size and can permanently lock away radioactive ions by displacing the existing sodium ions in the fibre.
"The fibres are in very thin layers, less than one nanometre in width, and the radioactive ions are attracted into the space between the layers," he said.
"Once the ceramic material absorbs a certain amount, the layers collapse to lock the radioactive ions inside."
Update: Physical Insights has more to add.