Performance of a SOFC fed by ethanol reforming products

doi:10.1016/S0167-2738(02)00361-2

Solid State Ionics

Volumes 152–153, December 2002, Pages 551-554

https://doi.org/10.1016/S0167-2738(02)00361-2 Get rights and content

Abstract

Performance of a Pt based anode solid oxide fuel cell (SOFC) fed with a gas mixture containing H₂, CO and CH₄ (molar ratio 1:1:1) produced by external ethanol decomposition was studied. Experiments were performed at atmospheric pressure in the temperature range 660–800 °C and anode potential vs. air −0.78 to −0.23 V. It was shown that at low temperature (660 °C), the outlet gas contained the products of complete oxidation of the gas mixture, while high temperature (800 °C) facilitated synthesis gas production.

Introduction

Ethanol, a product of biochemical conversion of biomass, is seriously considered as a fuel for fuel cells [1], [2]. Recently, Pd supported carbon catalysts were found showing high activity and selectivity for ethanol reforming [3] $C_{2} H_{5} OH = CH_{4} + CO + H_{2} .$

The gas mixture yielding reaction (1) can be used as a fuel for Solid Oxide Fuel Cell (SOFC). To design an external ethanol reforming SOFC, it is necessary to clarify which reactions occur on an anode fed with ethanol reforming products.

The present work reports the performance of a Pt anode SOFC fed with the mixture containing H₂, CO and CH₄ (molar ratio 1:1:1).

Section snippets

Materials and methods

The experimental apparatus included an electrochemical cell, potentiostat–galvanostat and gas chromatograph [4]. The electrochemical cell design was similar to that described in Ref. [5]. It was a tube closed at one end made of yttria stabilized zirconia (YSZ) electrolyte. The electrolyte tube was 100 mm in length, 10 mm in diameter and had a wall thickness of 0.6 mm. The Pt (working) electrode was supported on the inner surfaces of the tube. A reaction mixture of CH₄, CO, H₂ and He (N₂) was

Results and discussion

In the entire range of experimental conditions, the electrochemically pumped oxygen was converted completely, its outlet concentration was below the detection limit (<0.01 vol. %); the outlet gas contained CH₄, CO, CO₂, H₂ and H₂O.

Mass balances of carbon, oxygen and hydrogen were calculated by the following equations $r_{(CH_{4})_{in}} +r_{(CO)_{in}} =r_{(CH_{4})_{out}} +r_{(CO)_{out}} +r_{(CO_{2})_{out}}$ $r_{O_{2}} +1/2r_{(CO)_{in}} =1/2r_{(CO)_{out}} +r_{(CO_{2})_{out}} +1/2r_{(H_{2}O)_{out}}$ $2r_{(CH_{4})_{in}} +r_{(H_{2})_{in}} =2r_{(CH_{4})_{out}} +r_{(H_{2})_{out}} +r_{(H_{2}O)_{out}}$ where r_{(CH₄)_in}, r_{(CO)_in}, r_(H₂)in are the

Acknowledgements

The authors highly appreciate partial financial support provided by INTAS (Project No. 0897) and by INCO-Copernicus (Project No. ICA2-CT-2000-10030).

References (10)

G Maggio et al.
J. Power Sources
(1998)
V.V Galvita et al.
Appl. Catal. A: General
(1997)
G.L Semin et al.
Appl. Catal. A: General
(1999)
Design News, June 22 (1998)...
V.V Galvita et al.
Appl. Catal. A: General
(2001)

There are more references available in the full text version of this article.

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Performance of a SOFC fed by ethanol reforming products

Abstract

Introduction

Section snippets

Materials and methods

Results and discussion

Acknowledgements

J. Power Sources

Appl. Catal. A: General

Appl. Catal. A: General

Appl. Catal. A: General