Patent ID: 7758834

Claim:
A layered catalyst composite comprising: (a) a cordierite carrier; (b) a first layer deposited on the carrier, the first layer comprising: a palladium component deposited in an amount of up to about 200 g/ft 3 on a first refractory metal oxide support, and a first oxygen storage component comprising a ceria-zirconia composite with 40 to 50 weight % ceria, the ceria-zirconia composite being present in the first layer in an amount in the range of 0.75 to 0.9 g/in 3 ; (c) a second layer deposited on the first layer, the second layer comprising: a rhodium component deposited in an amount in the range of about 0.1 to about 50 g/ft 3 on a second refractory metal oxide support, and a second oxygen storage component comprising a ceria-zirconia composite with 35 to 45 weight % ceria, the ceria-zirconia composite being present in the second layer in an amount in the range of 0.7 to 0.9 g/in 3 ; and (a) a third layer deposited on the second layer, the third layer comprising: a palladium component deposited in an amount in the range of about 5 to about 100 g/ft 3 on a third refractory metal oxide support, and a third oxygen storage component comprising a ceria-zirconia composite with 40 to 50 weight % ceria, the ceria-zirconia composite being present in the third layer in an amount in the range of 0.25 to 0.4 g/in 3 .