Please use this identifier to cite or link to this item:
https://hdl.handle.net/20.500.14279/1677
Title: | An investigation of the NO/H2/O2 (Lean De-NOx) reaction on a highly active and selective Pt/La0.7Sr0.2Ce0.1FeO3 catalyst at low temperatures | Authors: | Andronikou, Ch. Costa, Costas Savva, Petros G. |
Major Field of Science: | Natural Sciences | Field Category: | Chemical Sciences | Keywords: | Catalysts;Low temperatures | Issue Date: | 25-Jun-2002 | Source: | Journal of Catalysis, 2002, vol. 209, no. 2, pp. 456–471 | Volume: | 209 | Issue: | 2 | Start page: | 456 | End page: | 471 | Journal: | Journal of Catalysis | Abstract: | A 0.1 wt% Pt supported on La0.7Sr0.2Ce0.1FeO3 solid (mixed oxide containing LaFeO3, SrFeO3-x, CeO2, and Fe2O3 phases) has been studied for the NO/H2/O2 reaction in the 100-400°C range. For a critical comparison, 0.1 wt% Pt was supported on SiO2, CeO2, and Fe2O3 and tested under the same reaction conditions. For the Pt/La0.7Sr0.2Ce0.1FeO3 catalyst a maximum in the NO conversion (83%) has been observed at 150°C with a N2 selectivity value of 93%, while for the Pt/SiO2 catalyst at 120°C (82% conversion) with a N2 selectivity value of 65% using a GHSV of 80,000 h-1 Low N2 selectivity values, less than 45%, were obtained with the Pt/CeO2 and Pt/Fe2O3 catalysts in the 100-400°C range. For the Pt/La0.7Sr0.2Ce0.1FeO3 catalyst, addition of 5% H2O in the feed stream at 140°C resulted in a widening of the operating temperature window with appreciable NO conversion and no negative effect on the stability of the catalyst during 20 h on stream. In addition, a remarkable N2 yield (93%) after 20 h on 0.25% NO/1% H2/5% O2/5% H2O/He gas stream at 140°C has been observed. Remarkable N2 selectivity values in the range of 80-90% have also been observed in the 100-200°C low-temperature range either in the absence or in the presence of water in the feed stream. A maximum specific integral reaction rate of 443.5 μmol N2/s·g of Pt metal was measured at 160°C during reaction with a 0.25% NO/1% H2/5% O2/5% H2O/He gas mixture. This value is higher by 90% than the corresponding one observed on the 0.1 wt% Pt/SiO2 catalyst at 120°C and it is the highest value ever reported for the reaction at hand in the 100-200°C low-temperature range on Pt-based catalysts. A TOF value of 13.4 × 10-2 s-1 for N2 formation was calculated at 110°C for the Pt/La0.7Sr0.2Ce0.1FeO3 catalyst. Temperature-programmed desorption (TPD) of NO and transient titration experiments of the catalyst surface following NO/H2/O2 reaction have revealed important information concerning the amount and chemical composition of active and inactive (spectator) adsorbed N-containing species present under reaction conditions. | URI: | https://hdl.handle.net/20.500.14279/1677 | ISSN: | 00219517 | DOI: | 10.1006/jcat.2002.3645 | Rights: | © Elsevier Science Attribution-NonCommercial-NoDerivs 3.0 United States |
Type: | Article | Affiliation: | University of Cyprus | Affiliation : | University of Cyprus University of Ioannina |
Publication Type: | Peer Reviewed |
Appears in Collections: | Άρθρα/Articles |
CORE Recommender
SCOPUSTM
Citations
119
checked on Nov 9, 2023
WEB OF SCIENCETM
Citations
50
112
Last Week
0
0
Last month
1
1
checked on Oct 29, 2023
Page view(s)
525
Last Week
0
0
Last month
5
5
checked on Dec 23, 2024
Google ScholarTM
Check
Altmetric
This item is licensed under a Creative Commons License