Ethanol steam reforming for hydrogen generation over structured catalysts

In situ photoelectron spectroscopy study of ethanol steam reforming over RhPd nanoparticles and RhPd/CeO2

“…The deconvolution of the Pd spectra adjusted well considering the contribution at 334.9 eV corresponding to Pd(0) and only one oxidized component at about 336.7 eV, which corresponds to highly oxidized Pd species.In contrast, Rh spectra recorded after calcination at 573 and 673 K required the contribution of the three Rh(0), Rh(I) and Rh(III) components, whereas after oxidation at 823 K Rh was completely oxidized. This is in accordance with the different stability of the metal oxides at different temperatures [19].After reduction with H 2 at 573 K (the temperature used for activating the catalyst for the ESR [9][10][11][12][13][14][15][16]), both metals reduced, as expected, but to a different degree. In the case of Pd, the component at higher binding energies corresponding to highly oxidized Pd disappeared and the spectrum was adjusted with only two components at 334.9 and 335.8 eV, corresponding to Pd(0) and Pd(II), respectively.…”

“…This has been attributed to the cooperative effect of the carbon-carbon bond scission capabilities of Rh, the hydrogen recombination ability of Pd, and the redox properties of CeO 2 , which promotes the activation of water molecules andprevents carbon deposition due to its oxygen storage capacity [7,8]. For these reasons, in recent years RhPd/CeO 2 has been used successfully in a variety of catalytic reactor configurations, such as conventional packed bed reactors [9,10], honeycombs [11], membrane reactors [12][13][14], and microreactors [15]. RhPd bimetallic nanoparticles (NPs) anchored over a reducible support such as CeO 2 constitute a complex system, where segregation of one of the metals towards the surface of the NPs, changes in the oxidation states, participation of surface oxygen atoms and hydroxyl species are all possible.…”

Hydrogen production by steam reforming of ethanol on a RhPt/CeO2/SiO2 catalyst: Synergistic effect of the Si:Ce ratio on the catalyst performance

“…This method produces a greater amount of H 2 per mole of ethanol [7] and is more economical compared to other methods, such as auto-thermal reforming or ethanol oxidation [8]. Different reaction routes (that depend on the reaction conditions, nature of the support, and the active phase) will produce a complex set of products, including hydrogen (H 2 ), carbon monoxide (CO), methane (CH 4 ), carbon dioxide (CO 2 ), ethane (C 2 H 6 ), ethylene (C 2 H 4 ), and acetaldehyde (CH 3 CHO) ( Table 1) [9][10][11][12].…”

“…Noble metals are promising candidates for the SRE [13]. Specifically, Rh-Pt bimetallic catalysts appear to have a high activity in the SRE and the water-gas shift reaction (WGSR) and a low susceptibility to coke formation [8,14]. In addition, the support plays a critical role in the SRE [15].…”

Hydrogen production by reforming of bio-alcohols

“… Rh-Co,(Churakova et al, 2010;Moura et al, 2012), Rh-Pd(L opez et al, 2013;L opez, Divins, & Llorca, 2012), and Rh-Pt(Cobo et al, 2013;Gutierrez et al, 2011) supported on CeO 2 , ZrO 2 , or La 2 O 3 .…”