Monday, Sept. 19, at 12:10 p.m. in Todd 334
The Gene and Linda Voiland School of Chemical Engineering and Bioengineering is hosting a seminar presented by János Szanyi, Staff Scientist, Institute for Integrated Catalysis, Pacific Northwest National Laboratory
Automotive Exhaust Gas Control by Catalysis
Increased fuel efficiency and decreased emission of environmentally harmful pollutants have been the two driving forces in the development of new, highly efficient, selective and durable catalysts for internal combustion engine applications. The rapid increase in the number of automobiles created a shortage in cheap fossil energy resources in the second half of the 20th century, and demanded the development of highly fuel efficient combustion engines. Meanwhile, growing societal consciousness about the negative consequences of automotive
pollution on our environment demanded the development of new catalytic technologies for mobile applications. Due to the fuel economy advantages of lean-burn engines, diesel-powered engines have been continuously gaining popularity, which, in turn, demanded renewed research aimed at developing novel catalytic approaches for lean-NOx reduction. The task is daunting, since any feasible catalyst needs to reduce NOx to N2 in the presence
of very large excess of O2. Traditional three-way catalysts worked rather efficiently at stoichiometric air-tofuel ratios, and removed both CO and unburned hydrocarbons by oxidation, and concomitantly reduced NOx to N2 . The optimum operational air-to-fuel ratio window of these types of catalysts, however, is very narrow (close to stoichiometry). Besides their limited window of operation, they also require the use of expensive platinum
group metals: Pd, Pt and Rh. The two technologies currently being used in lean-NOx reduction are lean NOx traps (LNT) and selective catalytic reduction of NOx by NH3. The catalysts used in these two processes and the operational principles of these two technologies are fundamentally different. In this seminar, after a brief introduction to automotive exhaust control catalysis, Dr. Szanyi is going to discuss the operation principles and the catalytic systems of these two technologies. He will discuss (mostly through his own research) the key
attributes of these catalytic processes. At the end of his talk, he will also briefly summarize some of the current challenges in automotive exhaust control catalysis.
