A recent study by Notre Dame scientists might mean rethinking how radioactive waste is stored and handled. Common scientific wisdom has said that all radioactive elements behave in a similar fashion when it comes to their physical and chemical properties. So much for common wisdom. ND’s Thomas Albrecht-Schmitt and his colleagues recently demonstrated that nothing could be further from the truth. The point may seem arcane, but it is critical since decisions about nuclear waste have been based on the common wisdom. “There’s been a long-held belief within the nuclear community that you can predict how plutonium, for instance, will behave by doing similar uranium chemistry,” the Massman chairman of Notre Dame’s civil engineering and geologic sciences department says. “But what we’ve shown in almost every case is that when you actually prepare the compounds, they’re all different. And that flies in the face of a lot of intuition.” Besides upsetting the common wisdom, the work also taught the scientists a potentially valuable lesson: It may be possible to simplify the process used to prepare radioactive waste for storage. Typically, radioactive waste is gathered up and encased in molten glass, which then hardens. Currently, each chemical form, or “oxidation state,” of the radioactive waste must be separately singled out for removal. “Everything has been targeted toward each specific chemical form of these dangerous elements, which can stay radioactive for up to 10 million years,” Albrecht-Schmitt says. “But as a result of this work, we now know that there are materials that wouldn’t care what chemical form you presented to them. They’d grab onto it no matter what.” And that could lead to simplifying the process and making it more economical.
_John Monczunski is an associate editor of_ Notre Dame Magazine.