COMBINING SCR WITH PNA FOR LOW-TEMPERATURE CONTROL OF EXHAUST GASES Russian patent published in 2019 - IPC B01D53/94 

FIELD: chemistry.

SUBSTANCE: present invention is aimed at the use of catalytic articles containing selective catalytic reduction (SCR) catalyst and passive NO_x adsorbing catalyst. Catalyst article includes SCR catalyst and adsorber catalyst. Each of these catalysts contains a metal molecular sieve, each with a different metal. Catalytic article can be closely related to other components in order to create efficiency advantage of NO_x from cold start to combined system DOC with SCRF. Higher conversion of NO_x also shown for lower arrangement due to accumulation of NO_x prior to initial ignition of SCR catalyst and selective monitoring of NH₃ breakthrough_, enabling increased filling levels of NH_3. Invention describes systems containing a catalytic article and methods of using the catalytic article. Systems may include flow system or monoliths of wall flow.

EFFECT: invention allows to create improved control of hydrocarbons and carbon oxide, as well as control over ammonia breakthrough.

117 cl, 19 dwg