METHOD FOR PRODUCTION OF AUTOMOTIVE THREE-WAY CATALYST Russian patent published in 2020 - IPC F01N3/20 B01D53/94 

FIELD: chemistry.

SUBSTANCE: disclosed is a method of producing automotive three-way catalyst. Method comprises steps of preparing an aqueous suspension containing a composition based on cerium and zirconium oxides, aluminium oxide, a modifier salt and a solution of a salt of precious metals; application of suspension onto substrate, drying and annealing. At the stage of preparing an aqueous suspension for grinding powders, compositions based on cerium and zirconium oxides and aluminium oxide are combined. Modifier salt used is barium nitrate or acetate. Addition of modifier to suspension is carried out before addition of precious metals. Addition of modifiers is carried out while stirring and maintaining the pH of the suspension in range of 4 to 7 units. PH is adjusted by adding an acetic acid solution if the pH is greater than 7 units and adding a solution of tetraethylammonium hydroxide in case the pH value is less than 4 units. Precious metals are added to the suspension after holding the suspension with modifier for at least 120 s.

EFFECT: invention discloses a method of producing automotive three-way catalyst.

4 cl, 1 dwg