METHOD OF OBTAINING CERIUM DIOXIDE Russian patent published in 2008 - IPC C01F17/00 C25B1/00 

FIELD: chemistry.

SUBSTANCE: proposed method involves putting a cerium (III) nitrate solution as a catholyte into a cathode chamber of an electrolysis cell, separated by a membrane from the anode chamber, filled with anolyte. Electrical current with density of 2.5-7.5 A/dm² is passed through the catholyte and anolyte. Cerium (III) nitrate undergoes hydrolyis with formation of a residue of cerium (IV) oxide at the cathode. Nitrate ions are released and migrate to the anode chamber. Nitric acid is concentrated in the anode chamber to 100-250 g/l content of HNO₃. An anion exchange membrane is used, and the anolyte used is a nitric acid solution. After washing and drying the cathode residue, cerium (IV) oxide is obtained. The invention allows for obtaining CeO₂ powder with particle size of 8-22 nm, cerium current output of 70-90% and extracting 97.6% of it in the final product with recycling of nitric acid at the same time.

EFFECT: limited number of used reagents and reduced power consumption.

5 cl, 6 ex