Hydrogen production from ethanol reforming: Catalysts and reaction mechanism

Hou, Tengfei; Zhang, Shaoyin; Chen, Yongdong; Wang, Dazhi; Cai, Wei

doi:10.1016/j.rser.2014.12.023

Cited by 263 publications

(193 citation statements)

References 201 publications

Supporting

Mentioning

184

Contrasting

Unclassified

Order By: Relevance

“…The development of stable catalysts is one of the most important issues in hydrogen production from ethanol, particularly for stoichiometric feed compositions with no excess H2O to remove carbon deposits [37], as being expected in real bioethanol samples obtained in Colombia. Four intrinsic deactivation modes have been identified: (i) coke formation; (ii) active metal sintering; (iii) active metal oxidation; and (iv) poisoning.…”

Section: Catalyst Characterizationmentioning

confidence: 99%

“…Acid sites in the support could promote ethanol dehydration to ethylene (Equation (8)). In contrast, basic sites and high oxygen electronic polarizability of the support are favorable for the dehydrogenation (Equation (3)) [37]. Although ceria, zirconia, and lanthana are recognized as basic supports, they might promote different SRE mechanisms alone and in combination with Rh-Pt active metals.…”

Section: Introductionmentioning

confidence: 99%

“…In general, the supports produced H2, CH4, and CO2, which can be related to the occurrence of hydrogenation/dehydrogenation reactions from the adsorbed ethoxy-species. O-vacancies present in CeO2-R favored the dehydration reaction (Equation (7)) through C-O cleavage, preventing the diffusion of C2 intermediates (like ethylene) [37], and stabilizing hydroxyl groups [27]. However, the lower amounts of H2 and CO compared with the catalysts shows that the supports are unable to further reform CH4 (Equation (6)), which is a more stable intermediate [27].…”

Section: Introductionmentioning

confidence: 99%

“…CeO2 was the most selective support toward H2 (Figure 1b), probably because it produces larger amounts of acetaldehyde that are subsequently reformed by Equation (7). Hou et al [37] proposed that the reaction mechanism over CeO2 and Ir/CeO2 catalysts is: ethanol→ethoxy species→acetaldehyde→ C2 species→C1 species. Ethoxy species could be dehydrogenated to acetaldehyde by the presence of -OH groups on the surface of the CeO2.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

et al. 2015

View full text Add to dashboard Cite

CeO2-, ZrO2-, and La2O3-supported Rh-Pt catalysts were tested to assess their ability to catalyze the steam reforming of ethanol (SRE) for H2 production. SRE activity tests were performed using EtOH:H2O:N2 (molar ratio 1:3:51) at a gaseous space velocity of 70,600 h −1 between 400 and 700 °C at atmospheric pressure. The SRE stability of the catalysts was tested at 700 °C for 27 h time on stream under the same conditions. RhPt/CeO2, which showed the best performance in the stability test, also produced the highest H2 yield above 600 °C, followed by RhPt/La2O3 and RhPt/ZrO2. The fresh and aged catalysts were characterized by TEM, XPS, and TGA. The higher H2 selectivity of RhPt/CeO2 was ascribed to the formation of small (~5 nm) and stable particles probably consistent of Rh-Pt alloys with a Pt surface enrichment. Both metals were oxidized and acted as an almost constant active phase during the stability test owing to strong metal-support interactions, as well as the superior oxygen mobility of the support. The TGA results confirmed the absence of carbonaceous residues in all the aged catalysts.

show abstract

Section: Catalyst Characterizationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Furthermore, the carbon-carbon bond breaking of ethanol requires higher reforming temperatures, and several competing reactions are also thermodynamically favorable [29]. Significant progress has been made in gaining insight into the reaction mechanisms of ethanol reforming [30]. Yet a consensus is still lacking due to the versatility of the ethanol reforming reaction where numerous combinations of catalyst and reaction conditions could be involved.…”

Section: Introductionmentioning

confidence: 99%

Hydrogen Production by the Steam Reforming of Bio-Ethanol over Nickel-Based Catalysts for Fuel Cell Applications

Chen¹,

Xu²

2017

IJSGE

View full text Add to dashboard Cite

Abstract:The bio-ethanol steam reforming over nickel-based catalysts when the temperature is within the range of 700 to 800 K is studied for fuel cell applications. The effect of operating conditions such as the temperature, space time, water-to-ethanol molar ratio, and oxygen-to-ethanol molar ratio on the product distribution is evaluated. The water-gas shift reaction is examined in the reforming process. Adjusting feed ratios to favor carbon removal from the surface is discussed in detail. It is shown that a nickel-supported-on-alumina catalyst completely converts bio-ethanol and high hydrogen yields are obtained. High temperatures and water-to-ethanol ratios can promote hydrogen production. There is no evidence that the water-gas shift reaction occurs over nickel-based catalysts. Carbon formation can be minimized by using high water-to-ethanol ratios. The presence of oxygen in the feed plays a favorable effect on the carbon deposition, but the carbon monoxide production is not reduced. There are several reaction pathways that could occur in the bio-ethanol steam reforming process, and the catalyst produces ethylene and acetaldehyde as intermediate products. The region of carbon formation depends on the temperature as well as the water-to-ethanol and oxygen-to-ethanol molar ratios. Finally, an overall reaction scheme as a function of temperature is proposed. The best catalysts appear to be those that are sufficiently basic to inhibit the dehydration of ethanol to ethylene, which subsequently polymerizes and causes coke formation.

show abstract

Hydrogen Production from Oxygenated Hydrocarbons: Review of Catalyst Development, Reaction Mechanism and Reactor Modeling

Mohamedali

Henni

Ibrahim

2017

Hydrogen Production Technologies

View full text Add to dashboard Cite

Hydrogen production from ethanol reforming: Catalysts and reaction mechanism

Cited by 263 publications

References 201 publications

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

Hydrogen Production by the Steam Reforming of Bio-Ethanol over Nickel-Based Catalysts for Fuel Cell Applications

Hydrogen Production from Oxygenated Hydrocarbons: Review of Catalyst Development, Reaction Mechanism and Reactor Modeling

Contact Info

Product

Resources

About