Combining the plasma reactor concept with a catalyst was considered to be a left field approach but is now moving to the top of the PNGV list, said Steve Barlow, a PNNL chemical physicist. Six years ago, this field of non-thermal plasma-activated catalysis didnt exist, but it appears to have many advantages over competing technologies. For example, our catalysts arent poisoned by sulfur in the exhaust, which is a challenge for other catalytic technologies. Since the beginning, we have worked to improve both the electrical discharge designs and the catalyst performance; the resulting hybrid system is vastly more efficient than what we started out with, Barlow said. It is also much more rugged and reliable. One surprising result has been the relative ease with which we have been able to move from the laboratory bench to actual engine testing. This gives us confidence in the soundness of our approach.
Recent prototype reactor tests conducted on a diesel engine at DOEs Oak Ridge National Laboratory show a 50 percent reduction of NOx. Researchers are continuing to refine the plasma reactor system, which received a patent in 1999, to achieve even greater reduction of NOx. PNGV targets are a 90 percent reduction in NOx emission
Contact: Gayle O'Donahue
DOE/Pacific Northwest National Laboratory