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Stable hydrogen production from ethanol through steam reforming reaction over nickel-containing smectite-derived catalyst.

Yoshida H, Yamaoka R, Arai M - Int J Mol Sci (2014)

Bottom Line: The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition.Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite.The Ni-containing smectite-derived catalyst contains, after H2 reduction, stable and active Ni nanocrystallites, and as a result, it shows a stable and high catalytic performance for the steam reforming of ethanol, producing H2.

View Article: PubMed Central - PubMed

Affiliation: . yoshida@chem.kumamoto-u.ac.jp.

ABSTRACT
Hydrogen production through steam reforming of ethanol was investigated with conventional supported nickel catalysts and a Ni-containing smectite-derived catalyst. The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition. Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite. The Ni-containing smectite-derived catalyst contains, after H2 reduction, stable and active Ni nanocrystallites, and as a result, it shows a stable and high catalytic performance for the steam reforming of ethanol, producing H2.

Show MeSH
Relationship between the crystallite size of Ni particles and the amount of CH4 formed (the amount of carbon deposits) per exposed Ni surface area.
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ijms-16-00350-f005: Relationship between the crystallite size of Ni particles and the amount of CH4 formed (the amount of carbon deposits) per exposed Ni surface area.

Mentions: XRD results for Ni35/SM and SM(Ni35) catalysts after reaction showed the peak at 26°, which was assignable to carbon deposition (Figure 4). On the other hand, the crystallite size of Ni particles determined by XRD did not change, as shown in Figure 4, indicating that the sintering of Ni was unlikely to occur under the present reaction conditions. Therefore, we conclude that the carbon deposition was the main cause of the catalyst deactivation. Carbon deposition was observed for all Ni catalysts used, and the amounts of the carbon deposited were determined from the total amount of CH4 detected during H2 heat treatment. Interestingly, the amount of carbon deposition per Ni surface area tended to decrease with the decreasing crystallite size of Ni particles (Figure 5), meaning that the formation of the Ni nanoparticle not only results in the increase of exposed Ni surface area, but also contributes to the decrease of the carbon deposition.


Stable hydrogen production from ethanol through steam reforming reaction over nickel-containing smectite-derived catalyst.

Yoshida H, Yamaoka R, Arai M - Int J Mol Sci (2014)

Relationship between the crystallite size of Ni particles and the amount of CH4 formed (the amount of carbon deposits) per exposed Ni surface area.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4307250&req=5

ijms-16-00350-f005: Relationship between the crystallite size of Ni particles and the amount of CH4 formed (the amount of carbon deposits) per exposed Ni surface area.
Mentions: XRD results for Ni35/SM and SM(Ni35) catalysts after reaction showed the peak at 26°, which was assignable to carbon deposition (Figure 4). On the other hand, the crystallite size of Ni particles determined by XRD did not change, as shown in Figure 4, indicating that the sintering of Ni was unlikely to occur under the present reaction conditions. Therefore, we conclude that the carbon deposition was the main cause of the catalyst deactivation. Carbon deposition was observed for all Ni catalysts used, and the amounts of the carbon deposited were determined from the total amount of CH4 detected during H2 heat treatment. Interestingly, the amount of carbon deposition per Ni surface area tended to decrease with the decreasing crystallite size of Ni particles (Figure 5), meaning that the formation of the Ni nanoparticle not only results in the increase of exposed Ni surface area, but also contributes to the decrease of the carbon deposition.

Bottom Line: The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition.Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite.The Ni-containing smectite-derived catalyst contains, after H2 reduction, stable and active Ni nanocrystallites, and as a result, it shows a stable and high catalytic performance for the steam reforming of ethanol, producing H2.

View Article: PubMed Central - PubMed

Affiliation: . yoshida@chem.kumamoto-u.ac.jp.

ABSTRACT
Hydrogen production through steam reforming of ethanol was investigated with conventional supported nickel catalysts and a Ni-containing smectite-derived catalyst. The former is initially active, but significant catalyst deactivation occurs during the reaction due to carbon deposition. Side reactions of the decomposition of CO and CH4 are the main reason for the catalyst deactivation, and these reactions can relatively be suppressed by the use of the Ni-containing smectite. The Ni-containing smectite-derived catalyst contains, after H2 reduction, stable and active Ni nanocrystallites, and as a result, it shows a stable and high catalytic performance for the steam reforming of ethanol, producing H2.

Show MeSH