METHOD OF AUTOMOTIVE CATALYST Russian patent published in 2012 - IPC B01J23/96 B82B1/00 B01J23/63 B01J21/04 B01J37/08 B01J38/60 

FIELD: process engineering.

SUBSTANCE: invention relates to production of automotive catalysts, particularly, to their recovery. Method or recovery comprises thermal decomposition of pyrocarbon, dissolution of platinoids by the mix of hydrochloric acid and nitric acid, or 30%- hydrogen peroxide in closed cycle. Note here that dissolution process is analysed for completeness of platinoids extraction while excess nitric acid and hydrogen peroxide are removed by reducing agents. To extract platinoids, acid solution is subjected to ionic flotation extraction by cationic surfactants. Then, extract with platinoid precursors is separated from acid solution containing cerium and aluminium ions to evaporate extractant. Platinoid precursors are dissolved in water to produce micellar solution, added is hydrazine hydrate to reduce platinoids in alkaline medium to metal nanoparticles on mixing by ultrasound. Dispersion is centrifuged to drain aqueous solution and rinse centrate by alcohol to proceed with centrifugation to obtain nanopowder of platinoids. Acid solution containing ions of cerium and aluminium is neutralised by potassium hydroxide to pH=8-9. Potash soap of higher carbonic acids is added to separate cerium and aluminium soaps. The latter are dissolved in micellar aqueous solution of sodium dodecylsulphate to make the mix of cerium and aluminium hydroxides and centrifuge obtained dispersion. Precipitate of cerium and aluminium hydroxides are rinsed by water to be centrifuged again so that precipitate is separated and air dried. Then, said precipitate is calcined at 400°C to obtain nanopowders CeO₂ and γ-Al₂O₃ and CeO₂.

EFFECT: new catalysts produced with no extra treatment.

5 cl, 2 ex