Propene epoxidation by nitrous oxide over Au–Cu/TiO2 alloy catalysts

Chimentão, R.J.; Medina, Françesc; Fierro, J.L.G.; Llorca, Jordi; Sueiras, J.E.; Cesteros, Yolanda; Salagre, Pilar

doi:10.1016/j.molcata.2007.05.008

Cited by 87 publications

(71 citation statements)

References 28 publications

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“…%) and the lowest Au/Cu molar ratio (1/3) presented the maximum catalytic activity and the highest selectivity to epoxidation. This agrees with the results previously reported by Chimentão et al [18] for similar catalysts with higher metallic content in the same reaction. They proposed that the copper content seemed to have a strong influence on dispersion and the catalytic performances of the metallic particles because, the higher the amount of copper, the lower the particle size of the metallic particles.…”

Section: Physico-chemical Characterizationsupporting

confidence: 94%

“…As regards the gold supported catalysts, they are very active, especially at low temperature which is one of the challenges to be overcome when designing PROX catalysts [14,15]. Combining copper and gold on several catalytic supports has been considered in some recent studies [18][19][20][21][22][23]. In these works, a synergistic effect between gold and copper was found and related to electronic interactions between both metals.…”

Section:  mentioning

confidence: 99%

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Gold supported on CuOx/CeO2 catalyst for the purification of hydrogen by the CO preferential oxidation reaction (PROX)

Laguna

Hernández

Arzamendi

et al. 2014

Fuel

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Hydrogen produced from the conversion of hydrocarbons or alcohols contains variable amounts of CO that should be removed for some applications such as feeding lowtemperature polymer electrolyte membrane fuel cells (PEMFCs). The CO preferential oxidation reaction (PROX) is particularly well-suited for hydrogen purification for portable and on-board applications. In this work, the synthesis and characterization by XRF, BET, XRD, Raman spectroscopy and H 2 -TPR of a gold catalyst supported on a copper-cerium mixed oxide (AuCeCu) for the PROX reaction are presented. The comparison of this catalyst with the copper-cerium mixed oxide (CeCu) revealed that the experimental procedure used for the deposition of gold gave rise to the loss of reducible material by copper lixiviation. However, the AuCeCu solid was more active for CO oxidation at low temperature. A kinetic study has been carried over the AuCeCu catalyst for the PROX reaction and compared with that of the CeCu catalyst. The main difference between the models affected the contribution of the CO adsorption term. This fact may be related to the surface electronic activity produced by the interaction of the cationic species in the AuCeCu solid, able to create more active sites for the CO adsorption and activation in the presence of gold.

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Section: Physico-chemical Characterizationsupporting

confidence: 94%

Section:  mentioning

confidence: 99%

Gold supported on CuOx/CeO2 catalyst for the purification of hydrogen by the CO preferential oxidation reaction (PROX)

Laguna

Hernández

Arzamendi

et al. 2014

Fuel

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“…Recently, many works have reported that supported Au-Cu catalysts can be efficient for the oxidation of benzyl alcohol to benzaldehyde [10], the partial oxidation of methanol to produce hydrogen [11] and the epoxidation of propene to propene oxide [12]. This has prompted us to consider whether bimetallic catalysts composed of gold and copper could give improved performance in the hydrochlorination of acetylene.…”

Section: Introductionmentioning

confidence: 99%

Kinetics of Acetylene Hydrochlorination over Bimetallic Au–Cu/C Catalyst

2009

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A kinetic model of the acetylene hydrochlorination over the bimetallic Au-Cu/C catalyst was obtained on the basis of kinetic data. DFT theoretical calculation and the kinetic model indicated the reaction probably proceeds via the Eley-Rideal mechanism in which gas phase HCl reacts with the adsorbed C 2 H 2 to produce vinyl chloride. Reaction conditions were optimized according to kinetics analyses. Under the optimized reaction conditions obtained, the bimetallic Au-Cu/C showed excellent performances with more than 99.5% conversion and selectivity and did not deactivate in 200 h on stream.

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Section: Introductionunclassified

“…Dentre os processos sugeridos para solucionar este problema (Park et al, 2009), a reação de SELOX do CO vem sendo considerada por muitos autores como uma alternativa bastante promissora (Gamarra et al, 2007). Os catalisadores mais utilizados para reação de SELOX do CO são aqueles à base de metais nobres, como Au (Harura e Date, 2001;Costello et al, 2002;Chimentã et al, 2007;Mozer et al, 2009).Outros autores estudaram a reação de SELOX do CO em perovskita de La dopada com Ce (Magalhães et al, 2010), bem como a oxidação de alcenos em presença de CoFe 2 O 4 (Kooti e Afshari, 2012). Cerca de 50 diferentes catalisadores já foram avaliados na reação em atmosfera rica em H 2 entre 25 e 250 °C e esses os estudos mostrara que os catalisadores à base de Au, Pt e Cu foram os mais ativos e seletivos (Chen et al, 2002).…”

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Aplicação de Nanoestruturas de óxidos de Co, Fe e Ferrita de Cobalto na Oxidação Seletiva do Monóxido de Carbono

Martins¹,

Carvalho²,

Chagas³

et al. 2015

Anais Do XX Congresso Brasileiro De Engenharia Química

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RESUMO -Óxidos de Co, Fe e ferrita de Co foram preparados, caracterizados e tiveram sua atividade avaliada na reação de oxidação seletiva do monóxido de carbono (SELOX). Os catalisadores foram preparados hidrotermicamente a 180 °C na presença de glicose. Em seguida, os catalisadores foram caracterizados por DRX, MEV, TPR, análise textural e, por fim, avaliados na reação em questão. Os resultados obtidos para os testes de reação com programação de temperatura (TPRe) revelaram que a nanoestrutura de ferrita de cobalto apresentou uma atividade superior para reação de SELOX do CO quando comparada às nanoestruturas dos óxidos de Fe e Co isolados. INTRODUÇÃOA crescente demanda global por energia limpa tem levado à procura de outras fontes alternativas como as células a combustível, em particular a de membrana polimérica eletrolítica, PEMFC (Proton Exchange Membrane Fuel Cel), por operar a baixas temperaturas e usar H 2 como combustível. Ocorre que a corrente rica em H 2 que a alimenta provém da reforma de hidrocarbonetos que gera uma mistura rica em H 2 , porém contendo uma quantidade relativamente elevada de CO que necessita ser reduzida a um nível máximo de 10 ppm a fim de não envenenar o eletrodo de Pt da célula. Dentre os processos sugeridos para solucionar este problema (Park et al., 2009), a reação de SELOX do CO vem sendo considerada por muitos autores como uma alternativa bastante promissora (Gamarra et al., 2007). Os catalisadores mais utilizados para reação de SELOX do CO são aqueles à base de metais nobres, como Au (Harura e Date, 2001;Costello et al., 2002;Chimentã et al., 2007;Mozer et al., 2009).Outros autores estudaram a reação de SELOX do CO em perovskita de La dopada com Ce (Magalhães et al., 2010), bem como a oxidação de alcenos em presença de CoFe 2 O 4 (Kooti e Afshari, 2012). Cerca de 50 diferentes catalisadores já foram avaliados na reação em atmosfera rica em H 2 entre 25 e 250 °C e esses os estudos mostrara que os catalisadores à base de Au, Pt e Cu foram os mais ativos e seletivos (Chen et al., 2002). Linhua et al. (2010)

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Propene epoxidation by nitrous oxide over Au–Cu/TiO2 alloy catalysts

Cited by 87 publications

References 28 publications

Gold supported on CuOx/CeO2 catalyst for the purification of hydrogen by the CO preferential oxidation reaction (PROX)

Gold supported on CuOx/CeO2 catalyst for the purification of hydrogen by the CO preferential oxidation reaction (PROX)

Kinetics of Acetylene Hydrochlorination over Bimetallic Au–Cu/C Catalyst

Aplicação de Nanoestruturas de óxidos de Co, Fe e Ferrita de Cobalto na Oxidação Seletiva do Monóxido de Carbono

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