METHOD OF PREPARING ZIRCONIUM OXIDES AND ZIRCONIUM BASED MIXED OXIDES Russian patent published in 2009 - IPC C01G25/02 

FIELD: chemistry.

SUBSTANCE: present invention is meant for chemical and automobile industry and can be used in making promoters and catalyst carriers for automobile systems of releasing exhaust gases. Zirconium hydroxide is precipitated from an aqueous solution of a zirconium salt by an alkali in the presence of a controlled amount of sulphate anions at ratio SO₄ ^2-/Zr⁴⁺ ranging from 0.3/1 to 1.5/1 and temperature not above 50°C. Sodium hydroxide can be used as the alkali. The aqueous solution can contain a salt of an alkaline, rare earth, transition metal, silicon, tin or lead, as well as their mixture. The hydroxide is calcinated, forming oxide, which practically does not contain sulphate. Specific surface area of the oxide after sintering at 1000°C is not less than 40 m²/g, and not less than 10 m²/g after sintering at 1100°C.

EFFECT: catalysts and ceramic objects made from these oxides are characterised by improved thermal stability and sintering ability.

24 cl, 1 tbl, 4 ex