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Blick, K.; Mitrelias, T.; Hargreaves, J. S. J.; Hutchings, Graham J.; Joyner, Richard W.; Kiely, Christopher J.; Wagner, Fritz

doi:10.1023/a:1019004110702

Cited by 67 publications

(36 citation statements)

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“…Unfortunately, no indication of selective C-H bond activation was observed. In line with several recent publications, these results cast doubts on the applicability of gold nanoparticles for selective alkane oxidation [50][51][52][53][54][55][56].…”

Section: Introductionsupporting

confidence: 74%

“…In high temperature (750°C) methane oxidation, gold was found to poison the methane coupling activity of MgO when present in a low concentration of 0.04 wt%. At higher loadings the selectivity towards the formation of CO and CO 2 increased [50]. In the liquid phase selective oxidation of cyclohexane, gold catalysts have been reported to maintain high selectivities even at conversion \10% [47,49].…”

Section: Resultsmentioning

confidence: 99%

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An Attempt to Selectively Oxidize Methane over Supported Gold Catalysts

Hereijgers

Weckhuysen

2011

Catal Lett

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The potential of supported gold catalysts for the selective gas-phase oxidation of methane to methanol with molecular oxygen was investigated. A broad range of supported gold-based catalyst materials was synthesized using reducible and non-reducible support materials. Although the formation of small gold nanoparticles was established for all catalyst materials, only a very low activity for the total oxidation of methane was observed, at temperatures [250°C. Since no traces of partial oxidation products, such as methanol, formaldehyde, formic acid, methyl formate, dimethyl ether and CO, were observed it was concluded that supported gold catalysts are not able to selectively oxidize methane to methanol under these experimental conditions.

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Section: Introductionsupporting

confidence: 74%

Section: Resultsmentioning

confidence: 99%

An Attempt to Selectively Oxidize Methane over Supported Gold Catalysts

Hereijgers

Weckhuysen

2011

Catal Lett

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“…Interestingly, the lattice spacing at the edges of the particle were expanded to compensate for the compression of the lattice constant at the particle interior. In their examination of Au on MgO using TEM, Blick and coworkers found that gold grew two-dimensionally at low coverages forming thin rafts before exhibiting more three dimensional growth at higher coverages of gold (299).…”

Section: Growth and Nucleation Of Goldmentioning

confidence: 99%

“…As mentioned previously, Blick et al observed the presence of two-dimensional particles of gold by TEM and Mössbauer spectroscopy. The authors found that for the oxidation of methane, 2-D rafts were essentially inactive and served only to block methane coupling reactions that probably occur on oxygen vacancies now covered by gold (299). The authors proposed that 3-D particles of gold were necessary for reaction and that the reaction took place at the particle support interface.…”

mentioning

confidence: 99%

Surface chemistry of catalysis by gold

et al. 2004

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IntroductionGold has long been regarded as an "inert" surface and bulk gold surfaces do not chemisorb many molecules easily. However, in the last decade, largely through the efforts of Masatake Haruta, gold particles, particularly those below 5 nm in size, have begun to garner attention for unique catalytic properties (1-8). In recent years, supported gold particles have been shown to be effective as catalysts for low temperature CO oxidation (9), selective oxidation of propene to propene oxide (10), water gas shift (11), NO reduction (12), selective hydrogenation of acetylene (or butadiene) (13)

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“…Over the last ten years, gold catalysts have been recognized as being active materials in oxidation reactions [1][2][3][4][5][6][7][8] and all the studies until now have revealed the strong dependence of gold catalyst activity on the type of support and the preparation method [9][10][11][12][13]. In liquid phase oxidation, gold catalysts have been shown as a good alternative for classical Pd and Pt based catalysts in terms of both selectivity and resistance to poisoning.…”

Section: Introductionmentioning

confidence: 99%

Gold based bimetallic catalysts for liquid phase applications

Dimitratos

Prati

2005

Gold Bull

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IntroductionOver the last ten years, gold catalysts have been recognized as being active materials in oxidation reactions [1][2][3][4][5][6][7][8] and all the studies until now have revealed the strong dependence of gold catalyst activity on the type of support and the preparation method [9][10][11][12][13]. In liquid phase oxidation, gold catalysts have been shown as a good alternative for classical Pd and Pt based catalysts in terms of both selectivity and resistance to poisoning. This traditionally represents a strong limitation to industrial application of those Pd and Pt based materials [14][15][16].During recent studies [17][18] we demonstrated the importance of the addition of gold to palladium/platinum metals in terms of their catalytic performance compared to the single metal catalysts. We found that a significant increase not only of the activity but also of the selectivity occurred when gold was added. Moreover, the resistance to poisoning (oxygen or by-product poisoning) using bimetallic catalysts was improved considerably. Particularly in the case of the oxidation of D-Sorbitol, we have also studied the effect of reaction conditions by changing the pressure of oxygen and pH conditions. The use of bimetallic systems allowed by increasing the oxygen pressure to be increased from 1 to 3 Atm (increasing oxygen solubility), without observing any poisoning due to over-oxidation and observing a significant increase in the reaction rate. Unfortunately a drawback of this experimental procedure low yield of monocarboxylate (gluconate/gulonate) due to the consecutive reactions. In this paper we have focused on the preparation of bimetallic systems using three different preparation methods (based on the sequence of metal addition and reduction) and also altering the molar ratio of the metals. As a model reaction we chose the selective oxidation of D-Sorbitol, (Scheme 1). Gold Based Bimetallic Catalysts for Liquid Phase ApplicationsNikolaos Dimitratos and Laura Prati* Dipartimento di Chimica Inorganica Metallorganica e Analitica e Centro C.N.R., AURICAT Programme, Centre of Excellence CIMAINA Unit, Università di Milano, via Venezian 21, 20133 Milano, Italy AbstractThe liquid phase oxidation of D-Sorbitol has been carried out in water using oxygen as the oxidant in the presence of gold based catalyst. Au/C, Pt/C and Pd/C monometallic systems were compared to bimetallic Au/Pd and Au/Pt on carbon. A strong synergistic effect was observed producing a significant increase of reaction rate. Moreover, the addition of gold to Pd or Pt catalyst produced a system more resistant to oxygen poisoning allowing it to work also under a moderate pressure. The effect of varying the molar ratio of the metals has also been studied.

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Cited by 67 publications

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An Attempt to Selectively Oxidize Methane over Supported Gold Catalysts

An Attempt to Selectively Oxidize Methane over Supported Gold Catalysts

Surface chemistry of catalysis by gold

Gold based bimetallic catalysts for liquid phase applications

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