Synthesis, characterization and application of ceria microspheres in removal of plutonium from low level waste

Ceramic materials like MnO₂, TiO₂, Na₂TiO₃, etc exhibit their potential as a sorbent of plutonium from low level waste. Present study involves investigation of sorption behavior of ceria microspheres prepared by sol-gel process. A number of batches of ceria microspheres were prepared where cerium concentration in the feed was varied in the range 1.45 to 1.25M while corresponding value of ratio of gelation agent to metal (R) was varied in the range 1.65 to 1.85. Despite using optimum composition only soft microspheres could be obtained which was not suitable for further processing. A number of washing schemes were tried using isopropyl alcohol and 1:1 mixture of isopropyl alcohol- 0.5 M NH₄OH in different steps and duration. Heating condition was also optimised by applying different heating rate, soaking temperature and duration of soaking. Finally, crack-free microspheres were obtained