Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation
Zirconia-supported vanadium oxide systems, with V2O5 loadings ranging from V/Zr ) 0.033-0.270 atom ratios (0.2-2 monolayers), were prepared by impregnation of a porous ZrO2 substrate with ammonium metavanadate solutions. The surface structures of air-calcined samples were elucidated by Raman and X-r...
| Authors: | ; ; ; ; |
|---|---|
| Format: | Article |
| Status: | Published version |
| Publication date: | 2002 |
| Country: | Argentina |
| Institution: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repository: | CONICET Digital (CONICET) |
| Language: | English |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/41530 |
| Online Access: | http://hdl.handle.net/11336/41530 |
| Access Level: | Open access |
| Keyword: | https://purl.org/becyt/ford/2.7 https://purl.org/becyt/ford/2 |
| _version_ | 1878404094290296832 |
|---|---|
| author | Pieck, Carlos Luis |
| author2 | Del Val, S. López Granados, M. Bañares, M. A. Fierro, J. L. G. |
| author2_role | author author author author |
| author_browse | Bañares, M. A. Del Val, S. Fierro, J. L. G. López Granados, M. Pieck, Carlos Luis |
| author_facet | Pieck, Carlos Luis Del Val, S. López Granados, M. Bañares, M. A. Fierro, J. L. G. |
| author_role | author |
| collection | CONICET Digital (CONICET) |
| description | Zirconia-supported vanadium oxide systems, with V2O5 loadings ranging from V/Zr ) 0.033-0.270 atom ratios (0.2-2 monolayers), were prepared by impregnation of a porous ZrO2 substrate with ammonium metavanadate solutions. The surface structures of air-calcined samples were elucidated by Raman and X-ray photoelectron spectroscopic techniques and thermal desorption methods. Some insight into how the bulk structures of these materials developed upon thermal treatment was derived from the X-ray diffraction patterns and temperature-programmed reduction. At low V content, surface-dispersed vanadium oxide species were formed, which produced the transformation of the ZrO2 support from the tetragonal phase into the monoclinic one. At higher vanadium oxide contents, a solid-state reaction between V2O5 and ZrO2 occurred, with subsequent formation of the ZrV2O7 phase, this being the major V-containing phase. The reactivity of these surface structures was examined by looking at their performance for the oxidation of o-xylene to phthalic anhydride. Activity tests indicated that surface vanadium oxide species were more active for the oxidation of o-xylene but had a lower selectivity to phthalic anhydride. |
| eu_rights_str_mv | openAccess |
| format | article |
| id | AR_fa2cc2cd736b06beae080f607f8da14a |
| identifier_str_mv | Pieck, Carlos Luis; Del Val, S.; López Granados, M.; Bañares, M. A.; Fierro, J. L. G.; Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation; American Chemical Society; Langmuir; 18; 7; 4-2002; 2642-2648 0743-7463 CONICET Digital CONICET |
| institution | Consejo Nacional de Investigaciones Científicas y Técnicas |
| instname_str | Consejo Nacional de Investigaciones Científicas y Técnicas |
| language | eng |
| network_acronym_str | AR |
| network_name_str | Argentina |
| oai_identifier_str | oai:ri.conicet.gov.ar:11336/41530 |
| publishDate | 2002 |
| publishDateSort | 2002 |
| publisher | American Chemical Society |
| publisherStr | American Chemical Society |
| reponame_str | CONICET Digital (CONICET) |
| spelling | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation Pieck, Carlos Luis Del Val, S. López Granados, M. Bañares, M. A. Fierro, J. L. G. https://purl.org/becyt/ford/2.7 https://purl.org/becyt/ford/2 Zirconia-supported vanadium oxide systems, with V2O5 loadings ranging from V/Zr ) 0.033-0.270 atom ratios (0.2-2 monolayers), were prepared by impregnation of a porous ZrO2 substrate with ammonium metavanadate solutions. The surface structures of air-calcined samples were elucidated by Raman and X-ray photoelectron spectroscopic techniques and thermal desorption methods. Some insight into how the bulk structures of these materials developed upon thermal treatment was derived from the X-ray diffraction patterns and temperature-programmed reduction. At low V content, surface-dispersed vanadium oxide species were formed, which produced the transformation of the ZrO2 support from the tetragonal phase into the monoclinic one. At higher vanadium oxide contents, a solid-state reaction between V2O5 and ZrO2 occurred, with subsequent formation of the ZrV2O7 phase, this being the major V-containing phase. The reactivity of these surface structures was examined by looking at their performance for the oxidation of o-xylene to phthalic anhydride. Activity tests indicated that surface vanadium oxide species were more active for the oxidation of o-xylene but had a lower selectivity to phthalic anhydride. Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; España Fil: Del Val, S.. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; España Fil: López Granados, M.. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; España Fil: Bañares, M. A.. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; España Fil: Fierro, J. L. G.. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; España American Chemical Society http://hdl.handle.net/11336/41530 Pieck, Carlos Luis; Del Val, S.; López Granados, M.; Bañares, M. A.; Fierro, J. L. G.; Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation; American Chemical Society; Langmuir; 18; 7; 4-2002; 2642-2648 0743-7463 CONICET Digital CONICET |
| spellingShingle | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation Pieck, Carlos Luis https://purl.org/becyt/ford/2.7 https://purl.org/becyt/ford/2 |
| status_str | publishedVersion |
| title | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| title_full | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| title_fullStr | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| title_full_unstemmed | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| title_short | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| title_sort | Bulk and Surface Structures of V2 O5 /ZrO2 Systems and Their Relevance for o -Xylene Oxidation |
| topic | https://purl.org/becyt/ford/2.7 https://purl.org/becyt/ford/2 |
| topic_facet | https://purl.org/becyt/ford/2.7 https://purl.org/becyt/ford/2 |
| url | http://hdl.handle.net/11336/41530 |