The Interfacial Effect on H2 Production from Oxidative Steam Reforming of Ethanol Over Rh/Ce1-xLaxO2-δ Nanocatalysts

Background: The production of hydrogen from catalytic reforming ethanol has attracted wide attention, which provides a promising way to replace fossil fuels with sustainable energy carriers. Methods: In this work, the Ce1-xLaxO2-δ solid solution (CL) supported Rh catalysts (nRh/CL, n = 0.5, 1 and 2 wt.%) were prepared by a traditional impregnation method with a variation of Rh loading. The different interface structure of nRh/CL catalysts and their catalytic performance in oxidative steam reforming (OSR) reaction were investigated. Results: Rh was loaded by the traditional impregnation method, and ethanol conversion and H2 yield declined in the order of 1%Rh/CL > 2%Rh/CL > 0.5%Rh/CL. Conclusion: The supports of the nRh/CL catalysts were confirmed to be Ce1-xLaxO2-δ solid solution, but only for the 1%Rh/CL catalyst, the Rh species were well-dispersed on the support and formed a Rh2O3//Ce1-xLaxO2-δ interface structure. The super-cell structure of Rh3+-O-RE3/4+ (RE = Ce, La) on the surface of 0.5%Rh/CL catalyst and the formation of interfacial Ce1-x-yLaxRhyO2-δ solid solution for 2%Rh/CL catalyst had effects on the self-activation of the nRh/CL catalysts. The typical lattice expansion of Ce1-xLaxO2-δ solid solution lowered the energy for migration. And the excellent hydrogen and oxygen mobility at the Rh//Ce1-xLaxO2-δ interface for 1%Rh/CL catalyst guaranteed the good catalytic performance for OSR at low temperature.

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Steam-reforming of ethanol for hydrogen production

Chemical Papers ◽

10.2478/s11696-010-0100-0 ◽

2011 ◽

Vol 65 (3) ◽

Cited By ~ 83

Author(s):

Ahmed Bshish ◽

Zahira Yaakob ◽

Binitha Narayanan ◽

Resmi Ramakrishnan ◽

Ali Ebshish

Keyword(s):

Hydrogen Production ◽

Steam Reforming ◽

Molar Ratio ◽

Ethanol Conversion ◽

Impregnation Method ◽

Reaction Conditions ◽

Oxide Supports ◽

Steam Reforming Of Ethanol ◽

Production Of Hydrogen ◽

Hydrogen Selectivity

AbstractProduction of hydrogen by steam-reforming of ethanol has been performed using different catalytic systems. The present review focuses on various catalyst systems used for this purpose. The activity of catalysts depends on several factors such as the nature of the active metal catalyst and the catalyst support, the precursor used, the method adopted for catalyst preparation, and the presence of promoters as well as reaction conditions like the water-to-ethanol molar ratio, temperature, and space velocity. Among the active metals used to date for hydrogen production from ethanol, promoted-Ni is found to be a suitable choice in terms of the activity of the resulting catalyst. Cu is the most commonly used promoter with nickel-based catalysts to overcome the inactivity of nickel in the water-gas shift reaction. γ-Al2O3 support has been preferred by many researchers because of its ability to withstand reaction conditions. However, γ-Al2O3, being acidic, possesses the disadvantage of favouring ethanol dehydration to ethylene which is considered to be a source of carbon deposit found on the catalyst. To overcome this difficulty and to obtain the long-term catalyst stability, basic oxide supports such as CeO2, MgO, La2O3, etc. are mixed with alumina which neutralises the acidic sites. Most of the catalysts which can provide higher ethanol conversion and hydrogen selectivity were prepared by a combination of impregnation method and sol-gel method. High temperature and high water-to-ethanol molar ratio are two important factors in increasing the ethanol conversion and hydrogen selectivity, whereas an increase in pressure can adversely affect hydrogen production.

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Sustainable Production of Hydrogen by Steam Reforming of Ethanol Using Cobalt Supported on Nanoporous Zeolitic Material

Nanomaterials ◽

10.3390/nano10101934 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1934

Author(s):

Javier Francisco da Costa-Serra ◽

Maria Teresa Navarro ◽

Fernando Rey ◽

Antonio Chica

Keyword(s):

Steam Reforming ◽

Zeolite Y ◽

Cobalt Catalysts ◽

Coke Deposition ◽

Bet Surface Area ◽

Ethanol Conversion ◽

Y Zeolite ◽

Steam Reforming Of Ethanol ◽

Production Of Hydrogen ◽

Hydrogen Selectivity

Cobalt catalysts supported on Y zeolite and mesoporized Y zeolite (Y-mod) have been studied in steam reforming of ethanol (SRE). Specifically, the effect of the mesoporosity and the acidity of the y zeolite as a support has been explored. Mesoporous were generated on Y zeolite by treatment with NH4F and the acidity was neutralized by Na incorporation. Four cobalt catalysts supported on Y zeolite have been prepared, two using Y zeolite without mesoporous (Co/Y, Co/Y-Na), and two using Y zeolite with mesoporous (Co/Y-mod and Co/Y-mod-Na). All catalysts showed a high activity, with ethanol conversion values close to 100%. The main differences were found in the distribution of the reaction products. Co/Y and Co/Y-mod catalysts showed high selectivity to ethylene and low hydrogen production, which was explained by their high acidity. On the contrary, neutralization of the acid sites could explain the higher hydrogen selectivity and the lower ethylene yields exhibited by the Co/Y-Na and Co/Y-mod-Na. In addition, the physicochemical characterization of these catalysts by XRD, BET surface area, temperature-programmed reduction (TPR), and TEM allowed to connect the presence of mesoporous with the formation of metallic cobalt particles with small size, high dispersion, and with high interaction with the zeolitic support, explaining the high reforming activity exhibited by the co/y-mod-Na sample as well as its higher hydrogen selectivity. It has been also observed that the formation of coke is affected by the presence of mesoporous and acidity. Both properties seem to have an opposite effect on the reforming catalyst, decreasing and increasing the coke deposition, respectively.

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Study on the Cu-Ni/Y2O3-ZrO2 Catalytic Performance in Ethanol Steam Reforming

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.2257 ◽

2012 ◽

Vol 512-515 ◽

pp. 2257-2261 ◽

Cited By ~ 1

Author(s):

Hong Da Wu ◽

Ying Gui Jia ◽

Yu Yin ◽

Lue Zhao

Keyword(s):

Steam Reforming ◽

Conversion Rate ◽

Carbon Deposition ◽

Catalytic Performance ◽

Precipitation Method ◽

Ethanol Conversion ◽

Ethanol Steam Reforming ◽

Impregnation Method ◽

Catalyst Composition ◽

Ethanol Steam

Y2O3-ZrO2 support was prepared by two-step precipitation method with ammonia and oxalic acid. A series of Cu-Ni/Y2O3-ZrO2 catalysts were prepared by impregnation method. The catalysts were investigated and then characterized by XRD and SEM results. The activity of catalysts in ethanol steam reforming was studied. The effects of the catalyst composition on the ethanol conversion rate were discussed and the catalysts inactivation phenomenon under the temperature ranging from 673K to 723K was then analyzed. The results show that 1Cu9Ni/1Y9Zr catalyst has higher activity in ethanol steam reforming, over which ethanol conversion rate is higher than 98% under the situation of 623K, while the inactivation of catalysts with Cu/Ni>3/7 at 673K~723K was caused by carbon deposition .

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A highly efficient and stable Ni/SBA-15 catalyst for hydrogen production by ethanol steam reforming

Progress in Reaction Kinetics and Mechanism ◽

10.1177/1468678319891842 ◽

2020 ◽

Vol 45 ◽

pp. 146867831989184

Author(s):

Xia An ◽

Jia Ren ◽

Weitao Hu ◽

Xu Wu ◽

Xianmei Xie

Keyword(s):

Steam Reforming ◽

Photoelectron Spectroscopy ◽

Nickel Nitrate ◽

Molar Ratio ◽

Linear Regression Method ◽

Impregnation Method ◽

X Ray ◽

Nickel Sulfamate ◽

Steam Reforming Of Ethanol ◽

Production Of Hydrogen

The production of hydrogen by steam reforming of ethanol was carried out on SBA-15-supported nano NiO catalyst synthesized by the equivalent-volume impregnation method with two different Ni sources (nickel nitrate and nickel sulfamate). The catalyst was characterized by N2 adsorption–desorption, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy to examine the physical and chemical properties. The activity tests were performed with the steam, with water/ethanol molar ratio ranging from 2:1 to 15:1, the N2 flow rate from 20 to 120 mL min−1 to determine the space-time, and the temperature range from 623 to 923 K on the two different Ni source catalysts. A favorable operating condition was established at 823 K using water/ethanol = 6 molar ratio and carrier gas (N2) flow of more than 50 mL min−1 for nickel nitrate source, but for nickel sulfamate source, the optimum temperature changed to 773 K and other conditions were the same as for the nickel nitrate source. After eliminating the influence of internal and external diffusion factors, an empirical power-law kinetic rate equation was derived from the experimental data. The non-linear regression method was used to estimate the kinetic parameter. The activation energy of the catalyst was then calculated, and the supported nickel nitrate and nickel sulfamate catalysts were 25.345 and 41.449 kJ mol−1, respectively, which was in agreement with the experimental and model-predicted results.

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Praseodymium-Doped Ce0.5Co0.5O2 Catalyst for Use on the Ethanol Steam Reforming to Produce Hydrogen

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.66.13 ◽

2016 ◽

Vol 66 ◽

pp. 13-24

Author(s):

Ya Ping Chen ◽

Chen Lung Chuang ◽

Pei Di Jeng ◽

Ruei Ci Wu ◽

Chen Bin Wang

Keyword(s):

Steam Reforming ◽

Oxygen Storage Capacity ◽

Catalytic Performance ◽

Oxygen Storage ◽

Ethanol Conversion ◽

Ethanol Steam Reforming ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Hydrogen Distribution ◽

Ethanol Steam

The catalytic performance of ethanol steam reforming (ESR) reaction was investigated on a praseodymium (Pr) dopant to modify Ce0.5Co0.5O2catalyst. The Ce0.5Co0.5O2catalyst was prepared by co-precipitation-oxidation method with NaOH precipitant and H2O2oxidant. Doped 5 and 10 wt% Pr (Pr5-Ce-Co and Pr10-Ce-Co) catalysts were prepared by an incipient wetness impregnation method and reduced at 250 and 400 °C (H250 and H400). All samples were characterized by using XRD, TPR, BET, EA, TG and TEM techniques at various stages of the catalyst. The results indicated that the doped Pr improved the activity and products distribution, and depressed the deposited carbon. The Pr10-Ce-Co-H400 sample was a highly active and stable among these catalysts, where the hydrogen distribution approached 72% at 475 °C and only minor C1(CO and CH4) species were detected. In addition, the ethanol conversion still remained complete, and the selectivity of hydrogen exceeded 70% during a 100 h time-on-stream test at 400 °C. The high oxygen storage capacity (OSC) and high accessible oxygen for this catalyst allowed oxidation/gasification of deposited carbon as soon as it formed, and less coke was detected.

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Steam reforming of ethanol for hydrogen production: influence of catalyst composition (Ni/Al2O3, Ni/Al2O3–CeO2, Ni/Al2O3–ZnO) and process conditions

Reaction Kinetics Mechanisms and Catalysis ◽

10.1007/s11144-021-01945-6 ◽

2021 ◽

Vol 132 (2) ◽

pp. 907-919

Author(s):

O. Shtyka ◽

Z. Dimitrova ◽

R. Ciesielski ◽

A. Kedziora ◽

G. Mitukiewicz ◽

...

Keyword(s):

Hydrogen Production ◽

Steam Reforming ◽

Catalyst Stability ◽

Feed Ratio ◽

Ethanol Conversion ◽

Process Conditions ◽

Catalyst Activation ◽

Catalyst Composition ◽

Activity Measurements ◽

Steam Reforming Of Ethanol

AbstractEthanol steam reforming was studied over Ni supported catalysts. The effects of support (Al2O3, Al2O3–ZnO, and Al2O3–CeO2), metal loading, catalyst activation method, and steam-to-ethanol molar feed ratio were investigated. The properties of catalysts were studied by N2 physisorption, TPD-CO2, X-ray diffraction, and temperature programmed reduction. After activity tests, the catalysts were analyzed by TOC analysis. The catalytic activity measurements showed that the addition either of ZnO SSor CeO2 to alumina enhances both ethanol conversion and promotes selectivity towards hydrogen formation. The same effects were observed for catalysts with higher metal loadings. High process temperature and high water-to-ethanol ratio were found to be beneficial for hydrogen production. An extended catalyst stability tests showed no loss of activity over 50 h on reaction stream. The TOC analysis of spent catalysts revealed only insignificant amounts of carbon deposit.

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