A Novel Exhaust After-Treatment Catalyst

Diesel engines are more efficient than gasoline powered engines, but have high emissions of particulate matter, nitrogen oxides and at times volatile organic compounds. New low temperature catalyst materials are needed for exhaust after-treatment systems that can meet the increasingly stringent emission regulations. TDA Research proposes to develop a new catalyst that will reduce nitrogen oxides, volatile organic compounds and carbon monoxide from diesel engine exhaust. The catalyst bed operates under the lean operating conditions of diesel engine exhaust at all times, providing a one-step solution that eliminates a wide range of air pollutants. The high activity of the catalyst also assures effective VOC abatement during cold starts. In Phase I, TDA developed a new catalyst for NOx and VOC removal. We showed the catalyst activity and contaminant removal efficiency under representative conditions. We also demonstrated the catalyst life through a 540 hr test without observing any signs of degradation in performance. The VOC oxidation capability of the catalyst was demonstrated across a wide range of contaminants ranging from CO, to olefins (e.g. ethylene) and alkanes (e.g. methane, propane). In a preliminary engineering analysis, we also showed the economic viability of the exhaust treatment system including the new catalyst. During Phase II we will continue to improve the performance of our catalyst by optimizing its chemical composition and mechanical integrity. We will scale-up its production using commercial manufacturing techniques. We will demonstrate the effective catalyst operation integrated with a small diesel engine (passenger car engine) using actual exhaust gas. We will also carry out a detailed engineering and cost analysis to fully assess the techno-economic viability of the new technology. Commercial Applications and Other Benefits There is an immediate commercial market for cost effective exhaust after treatment systems for diesel engines that can help meet the increasingly stringent U.S. emissions requirements and allow the expanded use of fuel efficient diesel vehicles.