Carbon formation on nickel and nickel-copper alloy catalysts
Autor(a) principal: | |
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Data de Publicação: | 1998 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/1822/1533 |
Resumo: | Equilibrium, kinetic and morphological studies of carbon formation in CH4+H2, CO, and CO+H2 gases on silica supported nickel and nickel-copper catalysts are reviewed. The equilibrium deviates in all cases from graphite equilibrium and more so in CO+CO2 than in CH4+H2. A kinetic model based on information from surface science results with chemisorption of CH4 and possibly also the first dehydrogenation step as rate controlling describes carbon formation on nickel catalyst in CH4+H2 well. The kinetics of carbon formation in CO and CO+H2 gases are in agreement with CO disproportionation as rate determining step. The presence of hydrogen influences strongly the chemisorption of CO. Carbon filaments are formed when hydrogen is present in the gas while encapsulating carbon dominates in pure CO. Small amounts of Cu alloying promotes while larger amounts (Cu : Ni ≥ 0.1) inhibits carbon formation and changes the morphology of the filaments ("octopus" carbon formation). Adsorption induced nickel segregation changes the kinetics of the alloy catalysts at high carbon activities. Modifications suggested in some very recent papers on the basis of new results are also briefly discussed. |
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Carbon formation on nickel and nickel-copper alloy catalystsKohlenstoffbildung auf Nickel und Nickel-Kupfer-LegierungskatalysatorenScience & TechnologyEquilibrium, kinetic and morphological studies of carbon formation in CH4+H2, CO, and CO+H2 gases on silica supported nickel and nickel-copper catalysts are reviewed. The equilibrium deviates in all cases from graphite equilibrium and more so in CO+CO2 than in CH4+H2. A kinetic model based on information from surface science results with chemisorption of CH4 and possibly also the first dehydrogenation step as rate controlling describes carbon formation on nickel catalyst in CH4+H2 well. The kinetics of carbon formation in CO and CO+H2 gases are in agreement with CO disproportionation as rate determining step. The presence of hydrogen influences strongly the chemisorption of CO. Carbon filaments are formed when hydrogen is present in the gas while encapsulating carbon dominates in pure CO. Small amounts of Cu alloying promotes while larger amounts (Cu : Ni ≥ 0.1) inhibits carbon formation and changes the morphology of the filaments ("octopus" carbon formation). Adsorption induced nickel segregation changes the kinetics of the alloy catalysts at high carbon activities. Modifications suggested in some very recent papers on the basis of new results are also briefly discussed.Center for Surface Reactivity.Wiley-VCH VerlagUniversidade do MinhoAlstrup, I.Tavares, M. T.Bernardo, C. A.Sørensen, O.Rostrup-Nielsen, J. R.19981998-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/1533eng"Materials and corrosion". ISSN 0947-5117. 49 (1998) 367-372.0947-511710.1002/(SICI)1521-4176(199805)49:5<367::AID-MACO367>3.0.CO;2-Minfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T12:19:46Zoai:repositorium.sdum.uminho.pt:1822/1533Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T19:12:44.554134Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Carbon formation on nickel and nickel-copper alloy catalysts Kohlenstoffbildung auf Nickel und Nickel-Kupfer-Legierungskatalysatoren |
title |
Carbon formation on nickel and nickel-copper alloy catalysts |
spellingShingle |
Carbon formation on nickel and nickel-copper alloy catalysts Alstrup, I. Science & Technology |
title_short |
Carbon formation on nickel and nickel-copper alloy catalysts |
title_full |
Carbon formation on nickel and nickel-copper alloy catalysts |
title_fullStr |
Carbon formation on nickel and nickel-copper alloy catalysts |
title_full_unstemmed |
Carbon formation on nickel and nickel-copper alloy catalysts |
title_sort |
Carbon formation on nickel and nickel-copper alloy catalysts |
author |
Alstrup, I. |
author_facet |
Alstrup, I. Tavares, M. T. Bernardo, C. A. Sørensen, O. Rostrup-Nielsen, J. R. |
author_role |
author |
author2 |
Tavares, M. T. Bernardo, C. A. Sørensen, O. Rostrup-Nielsen, J. R. |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade do Minho |
dc.contributor.author.fl_str_mv |
Alstrup, I. Tavares, M. T. Bernardo, C. A. Sørensen, O. Rostrup-Nielsen, J. R. |
dc.subject.por.fl_str_mv |
Science & Technology |
topic |
Science & Technology |
description |
Equilibrium, kinetic and morphological studies of carbon formation in CH4+H2, CO, and CO+H2 gases on silica supported nickel and nickel-copper catalysts are reviewed. The equilibrium deviates in all cases from graphite equilibrium and more so in CO+CO2 than in CH4+H2. A kinetic model based on information from surface science results with chemisorption of CH4 and possibly also the first dehydrogenation step as rate controlling describes carbon formation on nickel catalyst in CH4+H2 well. The kinetics of carbon formation in CO and CO+H2 gases are in agreement with CO disproportionation as rate determining step. The presence of hydrogen influences strongly the chemisorption of CO. Carbon filaments are formed when hydrogen is present in the gas while encapsulating carbon dominates in pure CO. Small amounts of Cu alloying promotes while larger amounts (Cu : Ni ≥ 0.1) inhibits carbon formation and changes the morphology of the filaments ("octopus" carbon formation). Adsorption induced nickel segregation changes the kinetics of the alloy catalysts at high carbon activities. Modifications suggested in some very recent papers on the basis of new results are also briefly discussed. |
publishDate |
1998 |
dc.date.none.fl_str_mv |
1998 1998-01-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/1822/1533 |
url |
http://hdl.handle.net/1822/1533 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
"Materials and corrosion". ISSN 0947-5117. 49 (1998) 367-372. 0947-5117 10.1002/(SICI)1521-4176(199805)49:5<367::AID-MACO367>3.0.CO;2-M |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Wiley-VCH Verlag |
publisher.none.fl_str_mv |
Wiley-VCH Verlag |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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