초록 ▼

A diesel exhaust aftertreatment system and method are provided. The system includes a lean NOx trap for reducing NOx and a transition metal-exchanged zeolite booster catalyst positioned downstream from the lean NOx trap for further reducing NOx. The lean NOx trap includes a NOx adsorbent material an

A diesel exhaust aftertreatment system and method are provided. The system includes a lean NOx trap for reducing NOx and a transition metal-exchanged zeolite booster catalyst positioned downstream from the lean NOx trap for further reducing NOx. The lean NOx trap includes a NOx adsorbent material and one or more platinum group metals, and has a platinum group metal loading of less than about 90 g/ft3. The aftertreatment system provides high NOx conversion over a broad temperature range without the use of ammonia as a major reductant.

대표청구항 ▼

What is claimed is: 1. An exhaust aftertreatment system comprising:a lean NOx trap positioned in an exhaust gas passage of an engine for receiving exhaust gas containing NOx and for reducing at least a portion of said NOx to N2; said lean NOx trap comprising one or more platinum group metals and hav

What is claimed is: 1. An exhaust aftertreatment system comprising:a lean NOx trap positioned in an exhaust gas passage of an engine for receiving exhaust gas containing NOx and for reducing at least a portion of said NOx to N2; said lean NOx trap comprising one or more platinum group metals and having a total platinum group metal loading of less than about 90 g/ft3; anda booster catalyst for enhancing NOx conversion without the use of ammonia as a primary reductant, said booster catalyst consisting essentially of one or more transition metal-exchanged zeolites positioned downstream from said lean NOx trap configured to further reduce NOx content in said exhaust gas; wherein said system does not include an NH3-SCR catalyst.