Journal
APPLIED CATALYSIS A-GENERAL
Volume 381, Issue 1-2, Pages 74-82Publisher
ELSEVIER
DOI: 10.1016/j.apcata.2010.03.012
Keywords
Hydrogen cyanide; Mechanism; Pt-Rh gauze; TAP-2
Categories
Funding
- Deutsche Forschungsgemeinschaft [KO 3561/1-1]
Ask authors/readers for more resources
Reaction pathways governing HCN selectivity in the oxidative coupling of methane and ammonia were investigated over three commercial Pt-Rh gauzes (fresh, activated, and spent) in the temporal analysis of products reactor with submillisecond-time resolution using isotopic traces. These gauzes differed in the extent of reaction-induced restructuring as well as impurity content. The ability of the gauzes to form HCN in the dual interactions of CH4 with NH3 or NO was compared considering the morphological differences of the gauzes. It was found that the progressive structural changes increased the gauze activity for methane conversion and facilitate the stabilization of methane fragments on the catalyst surface, but did not influence significantly the surface residence time of N-containing species. The well-known increase in HCN selectivity within first hours on-stream in the Andrussow process was suggested to be likely due to restructuring-induced stabilization of surface methane fragments. The decrease in the HCN selectivity after a stable phase of operation is mainly related to consecutive oxidation of HCN over iron oxide accumulated on the catalyst surface under industrial conditions of the Andrussow process. (C) 2010 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available