ZONED CATALYST FOR WASTE GAS TREATMENT Russian patent published in 2019 - IPC B01D53/94 B01J29/00 B01J23/72 B01J23/745 

FIELD: machine building.

SUBSTANCE: invention relates to a method and system of zoned catalysts for treating gaseous combustion products. System comprises a first SCR catalyst zone containing an iron-loaded medium- or large-pore molecular sieve with a first capacity for ammonia accumulation of not more than about 1.5 mmol/g of a catalyst, and a second SCR catalyst zone comprising a copper-loaded fine-pored molecular sieve with a second ammonia accumulation capacity of at least about 1.2 mmol/g of a catalyst, wherein the first SCR catalyst zone is located upstream of the SCR catalyst second zone relative to the normal waste gas flow through the system and the second ammonia accumulation capacity is greater than the first ammonia accumulation capacity.

EFFECT: invention provides high conversion of NO_x with minimum production of N₂O.

14 cl, 17 dwg