Journal ArticleDOI
Catalytic dry reforming of methane over high surface area ceria
TLDR
In this article, high surface area ceria (CeO 2) was synthesized by a surfactant-assisted approach, which has useful dry reforming activity for H 2 and CO production under solid oxide fuel cells (SOFCs) conditions.Abstract:
High surface area ceria (CeO 2 (HSA)), synthesized by a surfactant-assisted approach, was found to have useful dry reforming activity for H 2 and CO production under solid oxide fuel cells (SOFCs) conditions. The catalyst provides significantly higher reforming reactivity and excellent resistance toward carbon deposition compared to Ni/Al 2 O 3 and conventional low surface area ceria (CeO 2 (LSA)) under dry reforming conditions. These enhancements are due to the high redox property of CeO 2 (HSA). During the dry reforming process, the redox reactions between the gaseous components in the system and the lattice oxygen (O x ) take place on ceria surface. Among these reactions, the rapid redox reactions of carbon compounds such as CH 4 , and CO with lattice oxygen (CH 4 + O x → CO + H 2 + O x −1 and CO + O x = CO 2 + O x −1 ) can prevent the formation of carbon species from the methane decomposition and Boudard reactions even at low inlet carbon dioxide concentration. In particular, the dry reforming rate over CeO 2 (HSA) is proportional to the methane partial pressure and the operating temperature. Carbon dioxide presents weak positive impact on the methane conversion, whereas both carbon monoxide and hydrogen inhibit the reforming rate. The activation energies and reforming rates under the same methane concentration for CeO 2 toward the dry reforming are almost equal to the steam reforming as previously reported [1–4] . This result suggests the similar reaction mechanisms for both the steam reforming and the dry reforming over CeO 2 ; i.e., the dry reforming rate is governed by the slow reaction of adsorbed methane, or surface hydrocarbon species, with oxygen in CeO 2 , and a rapid gas–solid reaction between CO 2 and CeO 2 to replenish the oxygen.read more
Citations
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Journal ArticleDOI
Reforming of vegetable oil for production of hydrogen: A thermodynamic analysis
TL;DR: In this article, a Gibbs free energy minimization method was used to calculate the equilibrium products composition for the autothermal steam reforming and steam reforming of vegetable oils to synthesize hydrogen.
Journal ArticleDOI
Conversion of poisonous methanethiol to hydrogen-rich gas by chemisorption/reforming over nano-scale CeO2: The use of CeO2 as catalyst coating material
TL;DR: In this paper, a nano-scale CeO2 enables to convert poisonous methanethiol (CH3SH) to hydrogen-rich gas via the solid-gas reaction between CeO 2 and CH3SH under sufficient condition.
Journal ArticleDOI
Kinetics and mechanism of solar-thermochemical H2 and CO production by oxidation of reduced CeO2
Darwin Arifin,Alan W. Weimer +1 more
TL;DR: In this paper, the authors measured the H2 production rates over ceria powder, thermally reduced by laser irradiation, during oxidation by H2O and CO2 gases in a stagnation flow reactor.
Journal ArticleDOI
Tuning combined steam and dry reforming of methane for "metgas" production : A thermodynamic approach and state-of-the-art catalysts
TL;DR: In this paper, a thermodynamic equilibrium analysis of CSDRM has been performed using Gibbs free energy minimization where; (i) the effect of temperature (range: 200-1000°C), (ii) feed composition (stoichiometric ratio as compared to a feed under excess steam or excess carbon dioxide), (iii) pressure and, (iv) the presence of a gaseous diluent on coke yields, reactivity levels and selectivity towards “metgas” were investigated.
Journal ArticleDOI
Preparation and Characterization of Me2O3−CeO2 (Me = B, Al, Ga, In) Mixed Oxide Catalysts. 2. Preparation by Sol−Gel Method
TL;DR: In this paper, a combination of ceria mixed with another oxide from group III, using the sol-gel method, has been investigated, and the structural, textural, and surface properties of these catalysts have been fully characterized by means of a variety of techniques (Brunauer−Emmett−Teller, BET; X-ray diffraction analysis, XRD; Raman; scanning electron microscopy, SEM; thermogravimetric analysis, TG; and temperature-programmed reduction/oxidation, TPR-TPO).
References
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Journal ArticleDOI
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Journal ArticleDOI
The multiple roles for catalysis in the production of H2
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