EERE Success Story—Fundamental Studies in Catalysis Enabled the use of Efficient “Lean-Burn” Engines for Vehicle Transportation

May 7, 2015

You are here

Building on a catalysis research program sponsored by EERE’s Vehicles Technology Office (VTO) and DOE’s Office of Science, researchers at Cummins, Inc. and Pacific Northwest National Laboratory (PNNL) developed technology that has significantly reduced harmful emissions from many of today’s fuel-efficient diesel engines. The same research program also advanced the foundational understanding of catalyst structures and reactions, leading among other things to a 2009 publication in Science. The productive, multi-year partnership has continued to produce outcomes that are important for both industry and the science community.

The story began in the early 2000s.  Researchers at PNNL working on both basic energy sciences and vehicle technologies had been exploring how catalyst functions could improve emissions on gasoline-powered vehicles, using the unique suite of tools located in DOE’s Environmental Molecular Science Laboratory (EMSL). The research program had successfully identified specific structures that most efficiently convert NOx from conventional catalytic converters to the benign molecule, nitrogen.

Meanwhile, researchers at Cummins, an engine manufacturer, and Johnson Matthey, a supplier of catalysts, were studying a new material that provided the foundation for a new catalyst technology – the Lean-NOx Trap – to be used in lean-burn diesel engines. Designed for powerful vehicles like the Dodge Ram pickup, the Lean-NOx trap was intended to help these vehicles meet new emissions standards. However, while the new technology initially functioned well, its lifespan was far too short. Understanding why the technology wasn’t working required scientists to improve their understanding of the fundamental catalytic reactions. 

Based on the success of jointly funded catalysis research program at PNNL, Cummins and Johnson Matthey approached the Laboratory for help in developing a solution. In 2003, with funding from VTO, Cummins and PNNL began a collaborative, multi-year agreement to explore the Lean-NOx Trap material failures. Cummins and Johnson Matthey developed improved materials and new ways of operating the diesel engines that minimized the harmful catalyst changes in the Lean-NOx Trap technology. The breakthrough technology was first used in the 2007 Dodge Ram pickup, enabling it to meet the 2010 emission standard three years early.

In addition to supporting this market success story, researchers on the jointly funded EERE and Office of Science catalysis research program at PNNL have continued to utilize the instruments in EMSL to observe and model catalyst structural changes that help to understand the complex chemical and physical changes present in the real world energy systems. There are still many catalysis unknowns that could make for cleaner exhaust or higher performing materials that will lead to more fuel efficient vehicles.

See the Vehicle Technologies Office’s page on Emission Control for more information on its work in this area.

The Office of Energy Efficiency and Renewable Energy (EERE) success stories highlight the positive impact of its work with businesses, industry partners, universities, research labs, and other entities.