Californium: A useful way to recycle radioactive waste (if only it was less expensive)
Californium could recycle nuclear waste from power plants and weapons facilities. The material can be formed into storage containers that could recycle these highly-dangerous waste materials, providing into fuel for nuclear plants.
Thomas Albrecht-Schmitt of Florida State University is researching the use of the rare element to construct containers able to recycle nuclear waste back into fuel.
Californium is an element, number 98 on the periodic table, with the symbol Cf. It is a radioactive metal, synthesized in nuclear reactors, by bombarding curium with the nucleus of hydrogen atom. The material was first formed in 1950, and the University of California, Berkeley.
In experiments, californium was able to bond with other materials, changing the makeup of the substance stored within it. The element was also found to be extremely resistant to damage from radiation, making it ideal for the storage of radioactive waste.
Californium also has the ability to separate different elements in nuclear waste. This can recycle the fuel, for use in power plants.
The material forms bonds with negatively charged groups of atoms containing boron, known as borates. Electrons react in far different ways than expected when these bonds form.
One large obstacle to the development of these systems is the price of Californium. Albrecht-Schmitt's team had to pay $1.4 million for less than 0.00018 ounce of the element. Obtaining the material also took the researcher several years of negotiations with the Department of Energy. The material supplied to Albrecht-Schmitt was delivered by Oak Ridge National Laboratory. Funding for the program was paid for through an endowment.
Despite this enormous cost, the researcher believes his project has practical, as well as theoretical, benefits for mankind.
"We're changing how people look at californium and how it can be used," Albrecht-Schmitt said.
In addition to colleagues at Florida State, the team also worked with scientists from nine other universities, college and at Oak Ridge. David Dixon of the University of Alabama worked with a graduate student to develop a theoretical model to explain how californium could bond with different materials. Evgeny Alekseev and Wulf Depmeier worked in Germany, developing a better understanding of the way electrons behave in atoms of californium. Theory was brought into line with experiment through research performed by researchers at the Argonne National Laboratory in Illinois.
Research into the use of californium to recycle nuclear materials is profiled in the journal Nature Chemistry.