English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Water, which is an intrinsic part of the exhaust gas of combustion engines, strongly inhibits the methane oxidation reaction over palladium oxide-based catalysts under lean conditions and leads to severe catalyst deactivation. In this combined experimental and modeling work, we approach this challenge with kinetic measurements in flow reactors and a microkinetic model, respectively. We propose a mechanism that takes the instantaneous impact of water on the noble metal particles into account. The dual site microkinetic model is based on the mean-field approximation and consists of 39 reversible surface reactions among 23 surface species, 15 related to Pd-sites, and eight associated with the oxide. A variable number of available catalytically active sites is used to describe light-off activity tests as well as spatially resolved concentration profiles. The total oxidation of methane is studied at atmospheric pressure, with space velocities of 160,000 h−1 in the temperature range of 500–800 K for mixtures of methane in the presence of excess oxygen and up to 15% water, which are typical conditions occurring in the exhaust of lean-operated natural gas engines. The new approach presented is also of interest for modeling catalytic reactors showing a dynamic behavior of the catalytically active particles in general.

Microkinetic Modeling of the Oxidation of Methane Over PdO Catalysts—Towards a Better Understanding of the Water Inhibition Effect