Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts
| dc.contributor.author | Barhuizen, Andrew David | |
| dc.date.accessioned | 2024-04-10T09:40:49Z | |
| dc.date.available | 2024-04-10T09:40:49Z | |
| dc.date.issued | 2007 | |
| dc.date.updated | 2024-04-10T08:55:00Z | |
| dc.description.abstract | The classical deposition-precipitation synthesis from the group of Haruta (Tsubota eta/., 1995) -where the support is added to a pH adjusted solution of HAuCI4 and the system aged at constant pH and temperature - was examined, using ZnO as the support. Gold uptake by the support was confirmed to decrease with ageing pH, tending to zero as the IEPS of ZnO (- 9) is approached. Such behaviour is both qualitatively and quantitatively consistent with theory, which proposes that the magnitude and polarity of the charge on the support surface will determine the effective carrying capacity of that surface for an (an)ionic solution phase gold species. Decreasing post-calcination (120°C} gold crystallite size with increasing ageing pH [as reported by Haruta (1997)] was also observed (figure 11.2) - but it is not clear whether this resulted from pH dependent crystallization dynamics, from crystallite size being simply determined by the amount of deposited gold (which clearly decreases with increasing pH), or from chloride induced sintering during heat treatment (with chloride uptake by the support decreasing with increasing pH [Kung e t a /., 2003)). Nevertheless, gold deposition at pH 8 produced highly dispersed gold crystallites around 3.5 nm in diameter. | |
| dc.identifier.apacitation | Barhuizen, A. D. (2007). <i>Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts</i>. (). University of Cape Town ,Faculty of Science ,Department of Chemistry. Retrieved from http://hdl.handle.net/11427/39325 | en_ZA |
| dc.identifier.chicagocitation | Barhuizen, Andrew David. <i>"Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts."</i> ., University of Cape Town ,Faculty of Science ,Department of Chemistry, 2007. http://hdl.handle.net/11427/39325 | en_ZA |
| dc.identifier.citation | Barhuizen, A.D. 2007. Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts. . University of Cape Town ,Faculty of Science ,Department of Chemistry. http://hdl.handle.net/11427/39325 | en_ZA |
| dc.identifier.ris | TY - Thesis / Dissertation AU - BARKHUIZEN_DA AB - The classical deposition-precipitation synthesis from the group of Haruta (Tsubota eta/., 1995) -where the support is added to a pH adjusted solution of HAuCI4 and the system aged at constant pH and temperature - was examined, using ZnO as the support. Gold uptake by the support was confirmed to decrease with ageing pH, tending to zero as the IEPS of ZnO (- 9) is approached. Such behaviour is both qualitatively and quantitatively consistent with theory, which proposes that the magnitude and polarity of the charge on the support surface will determine the effective carrying capacity of that surface for an (an)ionic solution phase gold species. Decreasing post-calcination (120°C} gold crystallite size with increasing ageing pH [as reported by Haruta (1997)] was also observed (figure 11.2) - but it is not clear whether this resulted from pH dependent crystallization dynamics, from crystallite size being simply determined by the amount of deposited gold (which clearly decreases with increasing pH), or from chloride induced sintering during heat treatment (with chloride uptake by the support decreasing with increasing pH [Kung e t a /., 2003)). Nevertheless, gold deposition at pH 8 produced highly dispersed gold crystallites around 3.5 nm in diameter. DA - 2007 DB - OpenUCT DP - University of Cape Town KW - Chemistry LK - https://open.uct.ac.za PY - 2007 T1 - ETD: Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts TI - ETD: Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts UR - http://hdl.handle.net/11427/39325 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/39325 | |
| dc.identifier.vancouvercitation | Barhuizen AD. Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts. []. University of Cape Town ,Faculty of Science ,Department of Chemistry, 2007 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/39325 | en_ZA |
| dc.language.rfc3066 | eng | |
| dc.publisher.department | Department of Chemistry | |
| dc.publisher.faculty | Faculty of Science | |
| dc.publisher.institution | University of Cape Town | |
| dc.subject | Chemistry | |
| dc.title | Preparation and Water-Gas Shift Performance of Zinc Oxide Supported Dispersed Gold Catalysts | |
| dc.type | Thesis / Dissertation | |
| dc.type.qualificationlevel | Masters | |
| dc.type.qualificationlevel | Masters |