GS8.1 - RF measurement technique as a tool to understanding the gas loading on automotive catalysts

Event
17th International Meeting on Chemical Sensors - IMCS 2018
2018-07-15 - 2018-07-19
Vienna, Austria
Chapter
Gas Sensors 8 - Emerging Applications/Systems
Author(s)
D. Kubinski - Ford Research and Innovation Center, Dearborn, Michigan (USA), V. Malashchuk - Department of Functional Materials, University of Bayreuth, Bayreuth (Germany)
Pages
296 - 297
DOI
10.5162/IMCS2018/GS8.1
ISBN
978-3-9816876-9-9
Price
free

Abstract

The state of the oxygen storage material contained in automotive three-way catalysts (TWC’s)influences their ability to oxidize hydrocarbons and CO while simultaneously reducing nitrogen oxides (NOx). It has been demonstrated that the RF-microwave resonant method offers the ability to directly measure the oxygen storage on the TWC’s. Additionally, this technique has also been shown to be useful in other automotive applications such as measuring NH3 storage on diesel SCR catalysts, soot loading on particulate filters and NOx storage on traps. Here we give an overview of the various applications and present additional results for TWC’s. We demonstrate how the frequency of the resonant mode and its corresponding quality factor vary both with the oxidation state of the TWC and its temperature. We compare the temperature dependencies of these parameters with the measured catalytic efficiency. We show that the imaginary component of the catalyst’s dielectric permittivity, determined from the quality factor of the TE111 resonant mode, exhibits a large increase near the temperature at which the catalyst begins change its oxidation state with gas composition.

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