Separation of uranium and thorium from rare earths for rare earth production – A review

•A critical review has been provided on the separation of uranium and thorium from rare earths.•The methods used in rare earth industry during rare earth processing are extensively reviewed.•Potential methods for the separation of uranium and thorium from rare earths are also summarised.

Rare earths play critical roles in the applications of advanced materials. Recently, the recovery of rare earths from a variety of resources has gained much interest. Radioactive elements of uranium and thorium are usually associated with rare earth deposits. The separation of uranium and thorium from rare earths is often a big concern in rare earth industry in order to reasonably manage the radioactive nuclides. This paper reviews the technologies used for separating uranium and thorium from rare earths in rare earth production, particularly in China. Some potentially applicable methods, such as precipitation and solvent extraction for the separation of uranium and thorium from rare earths in different media were also reviewed.