It's more abundant than gold, and easier to find, due to the radiation signature it gives off as it decays. Generally, supplies of uranium have more than matched demand for it, though recently there have been fears this won't remain the case; as the world moves towards cleaner energy such as nuclear over fossil fuels, new supplies will have to be found.
We know where there's a lot of it – in the world's oceans – but there's a problem.
“There's a lot of uranium in the oceans, more than a thousand times more than what is found in the ground, but it's really diluted, so it's very difficult to extract," said Dr Jessica Veliscek Carolan, lead scientist on a study outlining a promising new extraction technique, in a statement. "The main challenge is that other substances in seawater, salt and minerals, such as iron and calcium, are present in much higher amounts than uranium."
The team looked into layered double hydroxide (LDH) materials, highly-modifiable materials that have shown promise for extracting uranium, as well as metals. LDH materials have layers with positive and negative charges, which can be tailored to extract specific substances – in this case, uranium.
Attempting to extract uranium under seawater-like conditions, the team refined their technique and found that when adding neodymium to the mix, it was especially efficient at picking out uranium over other elements abundant in the oceans.
As well as being useful for collecting new uranium, it could have the potential to clean up radioactive wastewater produced by the nuclear industry.
“There are additional benefits in that these materials are simple and inexpensive to make," Veliscek added, concluding that they could make a "cost-effective choice for large-scale uranium extraction."
The study is published in Energy Advances.