Separation of thorium and uranium in nitric acid solution using silica based anion exchange resin

•A novel silica based anion exchange resin to separate thorium and uranium.•Uranium and thorium could be separated and recovered rapidly due to the good kinetics of the silica based resin.•It could provide a way to recover few thorium from large amount of uranium.•It may be a solution to the 228Th and its radiological hazard of the reprocessed nuclear fuels.

To separate thorium and uranium in nitric acid solution using anion exchange process, a strong base silica-based anion exchange resin (SiPyR-N4) was synthesized. Batch experiments were conducted and the separation factor of thorium and uranium in 9 M nitric acid was about 10. Ion exchange chromatography was applied to separate thorium and uranium in different ratios. Uranium could be eluted by 9 M nitric acid and thorium was eluted by 0.1 M nitric acid. It was proved that thorium and uranium can be separated and recovered successfully by this method.