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

Applied Catalysis B: Environmental

et al. 2016

Self Cite

A copper-ceria bulk catalyst has been compared to a series of catalysts designed according to the as called "supported approach", corresponding to the dispersion of low content mixed copper-ceria oxide on alumina matrix. The principal characteristics of both types of catalysts are contemplated and the differences in their electronic and redox properties discussed in details. As a plus, the gold metal promotion of the catalysts is also envisaged. The advantages of the systems in the CO clean up reactions, WGS and CO-PrOx are commented. While the WGS activity appears to be ruled especially by the Cu/Ce surface to volume ratio, the CO-PrOx reaction is governed by the CuO loading. Gold addition provides benefits only at the low temperature WGS regime. Very importantly, the supported systems are always superior to the bulk configuration in terms of specific activity, a key factor from the catalyst's design perspective.

Section: Cuo-ceo2 Bulk Catalystmentioning

confidence: 99%

“…The success of CuO and CeO2 catalyst represents an interesting approach [25]. In fact, as recently reported AuCu alloys supported on ceria are rather efficient catalysts for the PrOx process [26].…”

Section: Introductionmentioning

confidence: 99%

WGS and CO-PrOx reactions using gold promoted copper-ceria catalysts: “Bulk CuO CeO2 vs. CuO CeO2/Al2O3 with low mixed oxide content”

Reina

Ivanova

Applied Catalysis B: Environmental

et al. 2016

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“…Herein, CuO-CeO 2 systems have demonstrated outstanding activity for both mentioned reactions and therefore they are intimately linked to the development of the last generation of hydrogen alimented fuel cells [12,15]. Barbato et al [11] reported very active catalyst for oxidation reactions based on CuO-CeO 2 catalysts prepared by solution combustion synthesis with respect to the typically ones synthesized by impregnation method [12][13][14][15]. Reina et al [12,15] reported that the catalytic system CuO-CeO 2 is very active and selective for CO oxidation and WGS reaction in the presence of a large amount of H 2 and that the selectivity increases when gold is also incorporated.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of Rh/MnO 2 -CeO 2 /Al 2 O 3 catalysts for CO-PrOx reaction

López-Cartés

2017

Molecular Catalysis

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Rh/MnO 2 -CeO 2 /Al 2 O 3 catalysts with different manganese-to-ceria ratios have been synthesized, characterized and tested in CO-PrOx reaction. The physicochemical properties of the solids were studied by XRD, Raman spectroscopy, BET surface area, H 2 -TPR, TGA-DTG and TEM. The differences observed in the textural, structural and redox properties were related to the Mn-toceria ratio of the samples. The segregation of Mn species was observed at high Mn-to-Ce ratios.In opposite way, MnO 2 -CeO 2 solid solutions were obtained at low Mn to Ce ones. In this last case, the physicochemical properties of the solids were favored by the intimate Rh-Ce-Mn contact. The effect of the Mn-Ce presence on Rh catalysts which promotes the catalytic behavior towards selective CO oxidation was observed to be better at low temperatures. At higher temperatures, Mn species promote the Reverse Water Gas Shift reaction, whilst ceria promotes the H 2 oxidation in the whole range of working temperatures.

“…may control the kind and rate of diffusion of the reagents and products along the channels. [18,19].…”

Section: Introductionmentioning

confidence: 99%

“…The manufacturing process of our microreactor prototype coated with 300 mg of catalyst [4,[18][19][20] is summarized in Figure 1. In the present work, this microreactor is named as MR300 and will be compared with a new block coated with 150 mg of catalyst, denoted as MR150.…”

Section: Introductionmentioning

confidence: 99%

Microreactors technology for hydrogen purification: Effect of the catalytic layer thickness on CuO /CeO2-coated microchannel reactors for the PROX reaction

Chemical Engineering Journal

González‐Castaño

Odriozola

2015

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Two blocks of microreactors composed by 100 microchannels and coated, respectively, with 150 and 300 mg of a CuO x /CeO 2 catalyst, were prepared and tested in the preferential oxidation of CO in presence of H 2 (PROX). The deposition of different amount of catalyst resulted in different catalytic layer thicknesses thus modifying the catalytic performances of the microreactor. The evaluation of the main reaction variables (the space velocity, the O 2 -to-CO ratio and the presence of H 2 O and/or CO 2 in the stream) was performed over both microreactors and compared to that of the parent powder catalyst. The least loaded microreactor, with a coating thickness around 10 µm, presented the highest CO conversion and selectivity levels at temperatures below 160 ºC.This result evidences i) the improvement of the catalytic performances got by the structuration of the powder catalyst and ii) the importance of the selection of the adequate thickness of the catalytic layer on the microreactor, which have not to exceed and optimal value. An adequate coating thickness allows minimizing the mass and heat transport limitations, thus resulting in the enhancement of the catalytic performance during the PROX reaction.