公开(公告)号：US20210053033A1

公开(公告)日：2021-02-25

申请号：US16547100

申请日：2019-08-21

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： Gongshin QI ,  Wei LI ,  Se H. OH ,  Ming YANG

IPC: B01J23/42 ,  B01J33/00 ,  B01D53/94 ,  F01N3/10

Abstract: The present disclosure provides a method for operating a three-way catalyst system at high temperatures. The method includes passing a high-temperature exhaust stream exiting an engine over a thermally stable three-way catalyst system including a metal oxide support; two or more catalytically active metals disposed on the support; and a porous metal oxide coating disposed on one or more exposed surfaces of the support. At least one of the catalytically active metals may be platinum (Pt). The method further includes reducing an amount of the nitrogen oxides (NOx), carbon monoxide (CO), and non-methane hydrocarbons (HCs) in an effluent stream exiting the thermally stable three-way catalyst system so that the effluent stream has a combined amount of nitrogen oxides (NOx) and non-methane hydrocarbons (HCs) of less than or equal to about 30 mg/mile and less than or equal to about 0.5 g/mile of carbon monoxide (CO).

公开(公告)号：US20190314804A1

公开(公告)日：2019-10-17

申请号：US16454709

申请日：2019-06-27

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： Xingcheng XIAO ,  Gongshin QI ,  Ryan J. DAY ,  Ming YANG

IPC: B01J37/03 ,  B01J35/00 ,  B01J23/44 ,  B01J37/08 ,  B01J37/18 ,  B01J23/42

Abstract: Catalyst systems that are resistant to high-temperature sintering and methods for preparing such catalyst systems that are resistant to sintering at high temperatures are provided. Methods of forming such catalyst systems include contacting a support having a surface including a catalyst particle with a solution comprising a metal salt and having an acidic pH. The metal salt is precipitated onto the surface of the support. Next, the metal salt is calcined to selectively generate a porous coating of metal oxide on the surface of the support distributed around the catalyst particle.