Patent Application

App. No. 18/252,243

Abstract

Claims (52)

1 . A zoned catalytic article, particularly useful for TWC, which comprises:

a) a catalyst composition coat comprising

i. a first zone of the catalyst composition coat, comprising a platinum group metal component consisting of a platinum component supported on a support; and

ii. a second zone of the catalyst composition coat, comprising a rhodium component and at least one of a platinum component and a palladium component supported individually or together on a support, and

b) a substrate;

wherein the first zone and the second zone of the catalyst composition coat are carried on a single piece of substrate or carried on respective pieces of substrate.

2 . The zoned catalytic article according to claim 1 , wherein the first zone is arranged upstream or downstream, preferably upstream from the second zone.

3 . The zoned catalytic article according to claim 1 , wherein the second zone comprises the rhodium component and the at least one of a platinum component and a palladium component as the major platinum group metal components, preferably substantially free of any PGMs other than platinum, palladium and rhodium.

4 . (canceled)

5 . The zoned catalytic article according to claim 1 , wherein the second zone includes a top layer and a bottom layer each containing one or more platinum group metal component selected from the rhodium component and the at least one of a platinum component and a palladium component, supported on respective supports.

6 . The zoned catalytic article according to claim 1 , wherein the second zone includes a top layer and a bottom layer and wherein the top layer contains a rhodium component and at least one of a platinum component and a palladium component supported individually or together on one or more supports, and the bottom layer contains a platinum component supported on one or more supports.

7 . The zoned catalytic article according to claim 1 , wherein the second zone includes a top layer and a bottom layer and wherein the top layer contains a platinum component, a palladium component and a rhodium component supported individually or together on one or more supports, and the bottom layer contains a platinum component supported on one or more supports.

8 . The zoned catalytic article according to claim 1 , wherein the first zone comprises a top layer and a bottom layer each containing the platinum group metal component supported on one or more supports.

9 . The zoned catalytic article according to claim 1 , wherein the support for each of the platinum component, palladium component and rhodium component is independently selected from refractory metal oxides, oxygen storage components and any combinations thereof.

10 . The zoned catalytic article according to claim 9 , wherein the refractory metal oxide is selected from baria doped alumina, lanthana doped alumina, eerie doped alumina, lanthana-zirconia doped alumina, baria-ceria doped alumina, and any combinations thereof, and wherein the oxygen storage component is selected from ceria-zirconia composite oxide and stabilized ceria-zirconia composite oxide.

11 . (canceled)

12 . The zoned catalytic article according to claim 1 , wherein the zoned catalytic article comprises;

a) a catalyst composition coat comprising

i. a first zone of the catalyst composition coat, including a top layer and a bottom layer, wherein each layer comprises a platinum group metal component consisting of a platinum component supported on one or more supports, and

ii. a second zone of the catalyst composition coat, including a top layer and a bottom layer, wherein the top layer contains a platinum component, a palladium component and a rhodium component supported individually or together on one or more supports, and the bottom layer contains a platinum component supported on one or more supports; and

b) a substrate,

wherein the first zone and the second zone of the catalyst composition coat are carried on a single piece of substrate or carried on respective pieces of substrate.

13 . The zoned catalytic article according to claim 1 , wherein the zoned catalytic article comprises:

a) a catalyst composition coat comprising

i. a first zone of the catalyst composition coat, including a top layer and a bottom layer, wherein

the top layer comprises a platinum group metal component consisting of a platinum component supported on a refractory metal oxide and an oxygen storage component;

the bottom layer comprises a platinum group metal component consisting of a platinum component supported on a refractory metal oxide,

ii. a second zone of the catalyst composition coat, including a top layer and a bottom layer, wherein

the top layer contains a palladium component supported on a refractory metal oxide, a rhodium component supported on a refractory metal oxide and an oxygen storage component, and a platinum component supported on respective supports of the palladium component and the rhodium component;

the bottom layer contains a platinum component supported on a refractory metal oxide and an oxygen storage component; and

b) a substrate,

wherein the first zone and the second zone of the catalyst composition coat are carried on a single piece of substrate or carried on respective pieces of substrate.

14 . The zoned catalytic article according to claim 1 , wherein the zoned catalytic article comprises:

a) a catalyst composition coat comprising

i. a first zone of the catalyst composition coat, including a top layer and a bottom layer, wherein

the top layer comprises a platinum group metal component consisting of a platinum component supported on a refractory metal oxide selected from ceria doped alumina and an oxygen storage component selected from ceria-zirconia composite oxide;

the bottom layer comprises a platinum group metal component consisting of a platinum component supported on a refractory metal oxide selected from baria-ceria doped alumina,

ii. a second zone of the catalyst composition coat, including a top layer and a bottom layer, wherein

the top layer contains a palladium component supported on a refractory metal oxide selected from baria doped alumina, a rhodium component supported on a refractory metal oxide selected from lanthana-zirconia doped alumina and an oxygen storage component selected from ceria-zirconia composite oxide, and a platinum component supported on respective supports of the palladium component and the rhodium component;

the bottom layer contains a platinum component supported on a refractory metal oxide selected from ceria doped alumina and an oxygen storage component selected from ceria-zirconia composite oxide; and

b) a substrate,

wherein the first zone and the second zone of the catalyst composition coat are carried on a piece of substrate or carried on respective pieces of substrate.

15 . The zoned catalytic article according to claim 1 , wherein the platinum component in the first zone is loaded in an amount of 1 to 250 g/ft 3 , or 5 to 150 g/ft 3 , or 10 to 100 g/ft 3 , or 30 to 80 g/ft 3 , or 40 to 70 g/ft 3 , calculated as platinum element.

16 . (canceled)

17 . The zoned catalytic article according to claim 1 , wherein the PGM components in the second zone are loaded in a total amount of 1 to 250 g/ft 3 , or 5 to 150 g/ft 3 , or 10 to 100 g/ft 3 , or 30 to 80 g/ft 3 , or 40 to 70 g/ft 3 , calculated as respective PGM element.

18 . The zoned catalytic article according to claim 1 , wherein the rhodium component in the second zone is loaded in an amount of 0.5 to 90 wt %, 0.5 to 70 wt %, or 0.5 to 50 wt %, or 1 to 20 wt %, or 3 to 10 wt % based on the total loading of the PGM components in the second zone.

19 . The zoned catalytic article according to claim 1 , wherein the ratio of the total Pt loading in the first zone and the total PGM loading in the second zone are in the range of 1:10 to 10:1, or 5:1 to 1:5, or 4:1 to 1:4, or 3:1 to 1:3, or 2:1 to 1:1.

20 . The zoned catalytic article according to claim 1 , wherein the substrate is a flow-through substrate or a wall-flow substrate.

21 . An exhaust treatment system, which comprises the zoned catalytic article as defined in claim 1 located downstream of an internal combustion engine, particularly a gasoline engine.

22 . The exhaust treatment system according to claim 21 , which is for motorcycle.

23 . A method for treating an exhaust stream, particularly from motorcycle engine, which includes contacting the exhaust stream with the zoned catalytic article as defined in claim 1 .

24 . (canceled)

Assignments (10)