Publication: Screening NOx Storage Performance

Screening NOx Storage Performance—Demonstrating a High Throughput Approach for Evaluating Emission Control Catalysts under Transient Conditions

Authors: Andreas Sundermann, Markus Kögel, Olga Gerlach

catalysts 2019, Vol 9, Issue 9 5679-5691

At hte the high throughput (HT) approach is applied in the field of environmental catalysis on a routine basis. Research programs for automotive applications require validated screening protocols for conditions relevant to engine exhaust as well as experimental measures to ensure quality control using statistical design of experiment. To illustrate the HT approach for a test protocol with dynamic feed switches in a 48-fold reactor, 15 model catalysts for lean NO_x traps (LNT) were prepared and screened fresh and after 800 ^◦C hydrothermal aging. In the fresh state, highest NO_x efficiency was found at 350–450 ^◦C. A ranking of BaO > SrO > CaO was found as the most active NO_x storage components when used as dopants on alumina. 800 ^◦C aging results in a severe performance loss. Using XRD and BET analysis, Pt sintering is identified as most likely cause. These findings agree well with results from conventional tests reported in the literature.