Diesel Exhaust Treatment Using Catalysts/Zeolites;Final rept. Jan 01-Jun 03

摘要

The pollution emitted by diesel engines contributes greatly to America's continuing air quality problems. The objective of this project was to develop and test a catalyst/zeolite system for its ability to effectively treat synthetic diesel exhaust primarily concentrating on the fate of hydrocarbons such as methane (CH4). This project involved proof-of-concept testing in the laboratory. The research project involved the following two major experimental tasks: (1) Identification of appropriate sorbents (e.g., zeolites) and catalysts to develop zeolites impregnated with catalyst(s) to treat diesel exhaust$ and (2) perform laboratory studies testing the catalyst/zeolite materials using synthetic diesel exhaust at various temperature conditions and diesel exhaust flow rates. Results were obtained on the system performance of the catalyst/zeolite system for its ability to degrade synthetic diesel exhaust. Despite the relatively low temperature involved in our study (compared to exhaust temperatures in the 600-800 deg F range from diesel engines), efficiencies typically ranged from -30 percent to -90 percent, depending on the particular combination of catalyst and zeolite involved. Using thermodynamic principles, the removal efficiency was estimated at 750 deg F. At this elevated temperature, removals of nearly 100 percent were estimated. System performance data was in close agreement with concentrations obtained using gas chromatography analyses (performed at The University of Alabama at Birmingham) and cermet micro sensor technology (performed at Argonne National laboratory). Based on the results obtained in this study, this concept involving treatment of diesel exhaust using catalysts/zeolites showed technical merit and is worth pursuing in the development phase.