AUTOMOTIVE CATALYST COMPOSITES HAVING TWO-METAL LAYER Russian patent published in 2018 - IPC B01J23/46 B01J23/44 F01N3/10 F01N3/20 

FIELD: chemical or physical processes.

SUBSTANCE: invention relates to automotive catalytic composites (version) whose catalytic material is effective for substantially simultaneous oxidation of carbon monoxide and hydrocarbons and the reduction of nitrogen oxides. According to the first version, the automotive catalytic composite includes: a catalytic material on a substrate, the catalytic material comprising a two-metal layer that comprises: a rhodium component on a first support which contains a refractory metal oxide component and, optionally, further comprises a first ceria-zirconia composite; a palladium component on a second support which comprises a second ceria-zirconia composite; one or more of such components as a promoter, stabiliser or binder; where the catalytic material is effective in a three-way conversion (TWC) for substantially simultaneous oxidation of carbon monoxide and hydrocarbons and reduction of nitrogen oxides, and where the total weight by weight of the first ceria-zirconia composite, if present, and the second ceria-zirconia composite in the two-metal layer is equal to or greater than the amount by weight of the refractory metal oxide component. According to a second version, the automotive catalyst composite comprises: a catalytic material on a substrate, the catalytic material comprising a two-metal layer which comprises: a rhodium component on a support, which is an activated alumina compound selected from a group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria; a palladium component thermally attached to the ceria-zirconia composite containing ceria in an amount that is in the range of 25-45% by weight of the ceria-zirconia composite; one or more of lanthana, baria and zirconia compounds; where the catalytic material is effective in a three-way conversion (TWC) for substantially simultaneous oxidation of carbon monoxide and hydrocarbons and reduction of nitrogen oxides, and wherein the weight ratio of the amount of the ceria-zirconia composite to the amount of the activated alumina compound in the two-metal layer is 4:1 or more. Invention also relates to an exhaust gas treatment system, a method for treating an exhaust gas and a method for manufacturing a catalytic composite.

EFFECT: technical result is improved catalytic performance.

15 cl, 4 dwg, 1 tbl, 9 ex