Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study
Decane-SCR-NO x , oxidation of NO and decane by molecular oxygen, and these reactions enhanced by hydrogen over Ag/alumina were investigated by monitoring of gaseous product composition, surface intermediates (in situ FTIR), and the state of silver (in situ UV–vis) under realistic reaction condition...
Gespeichert in:
| Veröffentlicht in: | Journal of catalysis 2005-06, Vol.232 (2), p.302-317 |
|---|---|
| Hauptverfasser: | , , , , , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | 317 |
|---|---|
| container_issue | 2 |
| container_start_page | 302 |
| container_title | Journal of catalysis |
| container_volume | 232 |
| creator | Sazama, P. Čapek, L. Drobná, H. Sobalík, Z. Dědeček, J. Arve, K. Wichterlová, B. |
| description | Decane-SCR-NO
x
, oxidation of NO and decane by molecular oxygen, and these reactions enhanced by hydrogen over Ag/alumina were investigated by monitoring of gaseous product composition, surface intermediates (in situ FTIR), and the state of silver (in situ UV–vis) under realistic reaction conditions in the steady-state and transient modes. It has been shown that oxidation of NO or decane by oxygen is greatly affected by the presence of decane or NO. Monodentate nitrates are formed preferentially and are more reactive compared with the bidentate species. Oxidation of decane mostly yields surface acetates, and the presence of NO
x
favors the formation of formates (acrylates). The reaction steps most enhanced by the addition of hydrogen to the SCR-NO
x
reaction are the transformations of the intermediate
CN species into
NCO and oxidation of the hydrocarbon to formates (acrylates). Although NO–NO
2 oxidation is also enhanced by hydrogen, this effect does not contribute to the increased rate of the SCR-NO
x
reaction. A small part of very reactive Ag
+ (estimated to be |
| doi_str_mv | 10.1016/j.jcat.2005.03.013 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_elsev</sourceid><recordid>TN_cdi_proquest_journals_195446468</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S002195170500120X</els_id><sourcerecordid>1179227191</sourcerecordid><originalsourceid>FETCH-LOGICAL-e808-3e9d9ccc548b13d91c829f4aac8e872111dcedc28c2acad739bf25db72ca52e33</originalsourceid><addsrcrecordid>eNot0M1Kw0AQB_BFFKwfL-Bp8Z50P5J0F7xIabVQFGr1umxmJ7pRN5pNir35Dr6hT2KqngaGP_8ZfoSccZZyxotxndZgu1QwlqdMpozLPTLiTLNEFDrbJyPGBE90zieH5CjGmjHO81yNyPssPNkA-Iqho01FHYINmNxNV8nNLf2gzQZbevk4ti_9qw-Wllv6tHVt84ghpSu00Pkm0GcfsPMQqQ2O-kCj73o6Xy9Wv4v7h-_Pr42PNHa9256Qg8q-RDz9n8dkPZ-tp9fJ8vZqMb1cJqiYSiRqpwEgz1TJpdMclNBVZi0oVBPBOXeADoQCYcG6idRlJXJXTgTYXKCUx-T8r_atbd57jJ2pm74Nw0XDdZ5lRVaoIXTxF8LhkY3H1kTwOHA43yJ0xjXecGZ2xKY2O2KzIzZMmoFY_gARLnIA</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>195446468</pqid></control><display><type>article</type><title>Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study</title><source>Elsevier ScienceDirect Journals Complete</source><creator>Sazama, P. ; Čapek, L. ; Drobná, H. ; Sobalík, Z. ; Dědeček, J. ; Arve, K. ; Wichterlová, B.</creator><creatorcontrib>Sazama, P. ; Čapek, L. ; Drobná, H. ; Sobalík, Z. ; Dědeček, J. ; Arve, K. ; Wichterlová, B.</creatorcontrib><description>Decane-SCR-NO
x
, oxidation of NO and decane by molecular oxygen, and these reactions enhanced by hydrogen over Ag/alumina were investigated by monitoring of gaseous product composition, surface intermediates (in situ FTIR), and the state of silver (in situ UV–vis) under realistic reaction conditions in the steady-state and transient modes. It has been shown that oxidation of NO or decane by oxygen is greatly affected by the presence of decane or NO. Monodentate nitrates are formed preferentially and are more reactive compared with the bidentate species. Oxidation of decane mostly yields surface acetates, and the presence of NO
x
favors the formation of formates (acrylates). The reaction steps most enhanced by the addition of hydrogen to the SCR-NO
x
reaction are the transformations of the intermediate
CN species into
NCO and oxidation of the hydrocarbon to formates (acrylates). Although NO–NO
2 oxidation is also enhanced by hydrogen, this effect does not contribute to the increased rate of the SCR-NO
x
reaction. A small part of very reactive Ag
+ (estimated to be <5%) is reduced to metallic charged
Ag
n
δ
+
clusters (
n
⩽
8
) during both the decane- and H
2/decane-SCR-NO
x
reactions. The number of
Ag
n
δ
+
clusters formed depends mainly on the level of NO conversion to nitrogen, regardless of whether the conversion level is attained by the addition of hydrogen or by an increased concentration of decane or oxygen in the feed. The time-resolved responses of NO
x
–N
2 conversion and of the number of
Ag
n
δ
+
clusters to the addition/removal of hydrogen from the reactants indicate that the
Ag
n
δ
+
clusters are mainly formed because of the reducing effect of adsorbed CH
x
O-containing reaction intermediates. The active sites are suggested to be single Ag
+ ions or small Ag
2O species. Hydrogen itself takes part in the SCR-NO
x
reaction. It is supposed that it dissociates, forms Ag-hydride, and enhances SCR-NO
x
by initiation radical reactions.</description><identifier>ISSN: 0021-9517</identifier><identifier>EISSN: 1090-2694</identifier><identifier>DOI: 10.1016/j.jcat.2005.03.013</identifier><language>eng</language><publisher>San Diego: Elsevier Inc</publisher><subject>Ag clusters ; Ag/alumina ; Hydrogen effect ; In situ FTIR ; In situ UV–vis ; SCR-NO x</subject><ispartof>Journal of catalysis, 2005-06, Vol.232 (2), p.302-317</ispartof><rights>2005 Elsevier Inc.</rights><rights>Copyright © 2005 Elsevier B.V. All rights reserved.</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://www.sciencedirect.com/science/article/pii/S002195170500120X$$EHTML$$P50$$Gelsevier$$H</linktohtml><link.rule.ids>314,776,780,3537,27901,27902,65306</link.rule.ids></links><search><creatorcontrib>Sazama, P.</creatorcontrib><creatorcontrib>Čapek, L.</creatorcontrib><creatorcontrib>Drobná, H.</creatorcontrib><creatorcontrib>Sobalík, Z.</creatorcontrib><creatorcontrib>Dědeček, J.</creatorcontrib><creatorcontrib>Arve, K.</creatorcontrib><creatorcontrib>Wichterlová, B.</creatorcontrib><title>Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study</title><title>Journal of catalysis</title><description>Decane-SCR-NO
x
, oxidation of NO and decane by molecular oxygen, and these reactions enhanced by hydrogen over Ag/alumina were investigated by monitoring of gaseous product composition, surface intermediates (in situ FTIR), and the state of silver (in situ UV–vis) under realistic reaction conditions in the steady-state and transient modes. It has been shown that oxidation of NO or decane by oxygen is greatly affected by the presence of decane or NO. Monodentate nitrates are formed preferentially and are more reactive compared with the bidentate species. Oxidation of decane mostly yields surface acetates, and the presence of NO
x
favors the formation of formates (acrylates). The reaction steps most enhanced by the addition of hydrogen to the SCR-NO
x
reaction are the transformations of the intermediate
CN species into
NCO and oxidation of the hydrocarbon to formates (acrylates). Although NO–NO
2 oxidation is also enhanced by hydrogen, this effect does not contribute to the increased rate of the SCR-NO
x
reaction. A small part of very reactive Ag
+ (estimated to be <5%) is reduced to metallic charged
Ag
n
δ
+
clusters (
n
⩽
8
) during both the decane- and H
2/decane-SCR-NO
x
reactions. The number of
Ag
n
δ
+
clusters formed depends mainly on the level of NO conversion to nitrogen, regardless of whether the conversion level is attained by the addition of hydrogen or by an increased concentration of decane or oxygen in the feed. The time-resolved responses of NO
x
–N
2 conversion and of the number of
Ag
n
δ
+
clusters to the addition/removal of hydrogen from the reactants indicate that the
Ag
n
δ
+
clusters are mainly formed because of the reducing effect of adsorbed CH
x
O-containing reaction intermediates. The active sites are suggested to be single Ag
+ ions or small Ag
2O species. Hydrogen itself takes part in the SCR-NO
x
reaction. It is supposed that it dissociates, forms Ag-hydride, and enhances SCR-NO
x
by initiation radical reactions.</description><subject>Ag clusters</subject><subject>Ag/alumina</subject><subject>Hydrogen effect</subject><subject>In situ FTIR</subject><subject>In situ UV–vis</subject><subject>SCR-NO x</subject><issn>0021-9517</issn><issn>1090-2694</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2005</creationdate><recordtype>article</recordtype><sourceid/><recordid>eNot0M1Kw0AQB_BFFKwfL-Bp8Z50P5J0F7xIabVQFGr1umxmJ7pRN5pNir35Dr6hT2KqngaGP_8ZfoSccZZyxotxndZgu1QwlqdMpozLPTLiTLNEFDrbJyPGBE90zieH5CjGmjHO81yNyPssPNkA-Iqho01FHYINmNxNV8nNLf2gzQZbevk4ti_9qw-Wllv6tHVt84ghpSu00Pkm0GcfsPMQqQ2O-kCj73o6Xy9Wv4v7h-_Pr42PNHa9256Qg8q-RDz9n8dkPZ-tp9fJ8vZqMb1cJqiYSiRqpwEgz1TJpdMclNBVZi0oVBPBOXeADoQCYcG6idRlJXJXTgTYXKCUx-T8r_atbd57jJ2pm74Nw0XDdZ5lRVaoIXTxF8LhkY3H1kTwOHA43yJ0xjXecGZ2xKY2O2KzIzZMmoFY_gARLnIA</recordid><startdate>20050610</startdate><enddate>20050610</enddate><creator>Sazama, P.</creator><creator>Čapek, L.</creator><creator>Drobná, H.</creator><creator>Sobalík, Z.</creator><creator>Dědeček, J.</creator><creator>Arve, K.</creator><creator>Wichterlová, B.</creator><general>Elsevier Inc</general><general>Elsevier BV</general><scope/></search><sort><creationdate>20050610</creationdate><title>Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study</title><author>Sazama, P. ; Čapek, L. ; Drobná, H. ; Sobalík, Z. ; Dědeček, J. ; Arve, K. ; Wichterlová, B.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-e808-3e9d9ccc548b13d91c829f4aac8e872111dcedc28c2acad739bf25db72ca52e33</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2005</creationdate><topic>Ag clusters</topic><topic>Ag/alumina</topic><topic>Hydrogen effect</topic><topic>In situ FTIR</topic><topic>In situ UV–vis</topic><topic>SCR-NO x</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Sazama, P.</creatorcontrib><creatorcontrib>Čapek, L.</creatorcontrib><creatorcontrib>Drobná, H.</creatorcontrib><creatorcontrib>Sobalík, Z.</creatorcontrib><creatorcontrib>Dědeček, J.</creatorcontrib><creatorcontrib>Arve, K.</creatorcontrib><creatorcontrib>Wichterlová, B.</creatorcontrib><jtitle>Journal of catalysis</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Sazama, P.</au><au>Čapek, L.</au><au>Drobná, H.</au><au>Sobalík, Z.</au><au>Dědeček, J.</au><au>Arve, K.</au><au>Wichterlová, B.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study</atitle><jtitle>Journal of catalysis</jtitle><date>2005-06-10</date><risdate>2005</risdate><volume>232</volume><issue>2</issue><spage>302</spage><epage>317</epage><pages>302-317</pages><issn>0021-9517</issn><eissn>1090-2694</eissn><abstract>Decane-SCR-NO
x
, oxidation of NO and decane by molecular oxygen, and these reactions enhanced by hydrogen over Ag/alumina were investigated by monitoring of gaseous product composition, surface intermediates (in situ FTIR), and the state of silver (in situ UV–vis) under realistic reaction conditions in the steady-state and transient modes. It has been shown that oxidation of NO or decane by oxygen is greatly affected by the presence of decane or NO. Monodentate nitrates are formed preferentially and are more reactive compared with the bidentate species. Oxidation of decane mostly yields surface acetates, and the presence of NO
x
favors the formation of formates (acrylates). The reaction steps most enhanced by the addition of hydrogen to the SCR-NO
x
reaction are the transformations of the intermediate
CN species into
NCO and oxidation of the hydrocarbon to formates (acrylates). Although NO–NO
2 oxidation is also enhanced by hydrogen, this effect does not contribute to the increased rate of the SCR-NO
x
reaction. A small part of very reactive Ag
+ (estimated to be <5%) is reduced to metallic charged
Ag
n
δ
+
clusters (
n
⩽
8
) during both the decane- and H
2/decane-SCR-NO
x
reactions. The number of
Ag
n
δ
+
clusters formed depends mainly on the level of NO conversion to nitrogen, regardless of whether the conversion level is attained by the addition of hydrogen or by an increased concentration of decane or oxygen in the feed. The time-resolved responses of NO
x
–N
2 conversion and of the number of
Ag
n
δ
+
clusters to the addition/removal of hydrogen from the reactants indicate that the
Ag
n
δ
+
clusters are mainly formed because of the reducing effect of adsorbed CH
x
O-containing reaction intermediates. The active sites are suggested to be single Ag
+ ions or small Ag
2O species. Hydrogen itself takes part in the SCR-NO
x
reaction. It is supposed that it dissociates, forms Ag-hydride, and enhances SCR-NO
x
by initiation radical reactions.</abstract><cop>San Diego</cop><pub>Elsevier Inc</pub><doi>10.1016/j.jcat.2005.03.013</doi><tpages>16</tpages></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0021-9517 |
| ispartof | Journal of catalysis, 2005-06, Vol.232 (2), p.302-317 |
| issn | 0021-9517 1090-2694 |
| language | eng |
| recordid | cdi_proquest_journals_195446468 |
| source | Elsevier ScienceDirect Journals Complete |
| subjects | Ag clusters Ag/alumina Hydrogen effect In situ FTIR In situ UV–vis SCR-NO x |
| title | Enhancement of decane-SCR-NO x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV–vis study |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-06T06%3A38%3A43IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_elsev&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Enhancement%20of%20decane-SCR-NO%20x%20over%20Ag/alumina%20by%20hydrogen.%20Reaction%20kinetics%20and%20in%20situ%20FTIR%20and%20UV%E2%80%93vis%20study&rft.jtitle=Journal%20of%20catalysis&rft.au=Sazama,%20P.&rft.date=2005-06-10&rft.volume=232&rft.issue=2&rft.spage=302&rft.epage=317&rft.pages=302-317&rft.issn=0021-9517&rft.eissn=1090-2694&rft_id=info:doi/10.1016/j.jcat.2005.03.013&rft_dat=%3Cproquest_elsev%3E1179227191%3C/proquest_elsev%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=195446468&rft_id=info:pmid/&rft_els_id=S002195170500120X&rfr_iscdi=true |