Kinetics of NH<sub>3</sub> Desorption and Diffusion on Pt: Implications for the Ostwald Process
Dmitriy Borodin, Igor Rahinov, Oihana Galparsoro, Jan Fingerhut, Michael Schwarzer, Kai Golibrzuch, Georgios Skoulatakis, Daniel J. Auerbach, Alexander Kandratsenka, Dirk Schwarzer, Theofanis N. Kitsopoulos, Alec M. Wodtke
Abstract
's binding energy preference for steps over terraces on Pt (0.23 ± 0.03 eV). The ratio of the diffusion barrier to desorption energy is ∼0.65, in violation of the so-called 12% rule. Using our derived diffusion/desorption rates, we explain why established rate models of the Ostwald process incorrectly predict low selectivity and yields of NO under typical reactor operating conditions. Our results suggest that mean-field kinetics models have limited applicability for modeling the Ostwald process.
Topics & Concepts
ChemistryDesorptionOstwald ripeningDiffusionDiffusion processThermodynamicsActivation energyKineticsReaction rate constantSurface diffusionTransition state theoryPartition (number theory)Physical chemistryAnalytical Chemistry (journal)Chemical physicsAdsorptionChromatographyPhysicsKnowledge managementCombinatoricsComputer scienceQuantum mechanicsInnovation diffusionMathematicsAmmonia Synthesis and Nitrogen ReductionCatalytic Processes in Materials ScienceAdvanced Chemical Physics Studies