Plasma Catalysis for NOx Reduction from Light-Duty Diesel Vehicles
The control of NOx (NO and NO2) emissions from so-called ‘lean-burn’ vehicle engines remains a challenge. In this program, we have been developing a novel plasma/catalyst technology for the remediation of NOx under lean (excess oxygen) conditions, specifically for compression ignition direct injection (CIDI) diesel engines that have significant fuel economy benefits over conventional stoichiometric gasoline engines. Program efforts included: (1) improving the catalyst and plasma reactor efficiencies for NOx reduction; (2) studies to reveal important details of the reaction mechanism(s) that can then guide our catalyst and reactor development efforts; (3) evaluating the performance of prototype systems on real engine exhaust; and (4) studies of the effects of the plasma on particulate matter (PM) in real diesel engine exhaust. Figure 1 is a conceptual schematic of a plasma/catalyst device, which also shows our current best understanding of the role of the various components of the overall device for reducing NOx from the exhaust of a CIDI engine. When this program was initiated, it was not at all clear what the plasma was doing and, as such, what class of catalyst materials might be expected to produce good results. With the understanding of the role of the plasma (as depicted in Figure 1) obtained in this program, faujasite zeolite-based catalysts were developed and shown to produce high activity for NOx reduction of plasma-treated exhaust in a temperature range expected for light-duty diesel engines. These materials are the subject of a pending patent application, and were recognized with a prestigious R&D100 Award in 2002. In addition, PNNL staff were awarded a Federal Laboratory Consortium (FLC) Award in 2003 “For Excellence in Technology Transfer”. The program also received the DOE’s 2001 CIDI Combustion and Emission Control Program Special Recognition Award and 2004 Advanced Combustion Engine R&D Special Recognition Award.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 966326
- Report Number(s):
- PNNL-14926; VT0401000; TRN: US200921%%359
- Resource Relation:
- Related Information: Advanced Combustion Engine Research & Development, 2004 Annual Progress Report, 180-183
- Country of Publication:
- United States
- Language:
- English
Similar Records
SELECTIVE REDUCTION OF NOX IN OXYGEN RICH ENVIRONMENTS WITH PLASMA-ASSISTED CATALYSIS: CATALYST DEVELOPMENT AND MECHANISTIC STUDIES
E. Plasma Catalysis for NOx Reduction from Light-Duty Diesel Vehicles