When it comes to cleaning up radioactive materials after a spill, scientists need to get pretty creative. From robots to bacteria, anything that will remove dangerous radiation from the environment is a step in the right direction. Researchers from Rice University and Lomonosov Moscow State University recently discovered a new tool to help with hazardous material removal: It turns out that graphene oxide is able to clump toxins together, making it easy for them to be separated from water. The resulting compound can then later be melted down into a slag and sequestered.
With its large surface area, graphene oxide is a champ at absorbing and retaining toxins. Bentonite clays and activated carbon are currently the substances of choice, but flakes of graphene oxide may soon replace the materials as they are more efficient and clump hazardous isotopes and metals more quickly. In a lab test, microscopic flakes of graphene oxide were added to water containing uranium and plutonium as well substances that were shown to negatively affect their absorption like calcium and sodium. Within minutes, the flakes pulled in the radionuclides and separated it from the liquid. The process was effective across a large range of pH values. The resulting graphene oxide and toxin combination was later skimmed off, and has the option of either being burned or reused.
The results of the study, which were recently published in The Royal Society of Chemistry journal, Physical Chemistry Chemical Physics, could represent a significant breakthrough in dealing with radioactive waste. In addition to being a valuable weapon in the fight clean up disasters like the Fukushima Daiichi meltdown, graphene oxide has the potential to help deal with the runoff generated in hydraulic fracturing and the mining of rare earth metals. Being able to filter out dangerous chemicals and isotopes on site could aid in environmental remediation but also save a lot of money. The low-cost and biodegradable qualities of the material also makes it an attractive material for use in permeable reactive barriers used for groundwater remediation.
+ Rice University