An investigation of fuel composition and flow‐rate effects in a H₂S fuelled sofc: Experiments and thermodynamic analysis

Abstract

Hydrogen sulphide (H2S)‐fuelled solid oxide fuel cells (SOFCs) can potentially generate useful electrical energy while disposing of H2S, a toxic by‐product of the fossil fuel industry, on site. Experimental results from H2S fuelled SOFCs exhibit characteristics, for example, an unusual dependence of cell performance on fuel composition and flow‐rate, which are poorly explained in the literature. In this work we: (a) present results for experiments where the composition and flow‐rates were varied for both the fuel and oxidant streams to analyse their effect on fuel cell performance, and (b) develop and use a thermodynamic analysis to help understand these experimental results. Through this work, we shed further light on two basic questions unanswered so far, (1) Why does the flow‐rate of the fuel affect the open circuit potential of the fuel cell? (2) Which of the chemical species present in the fuel is oxidised on the anode? Our experiments and analysis suggest that H2S, and not H2 produced from H2S dissociation, is preferentially electro‐oxidised on the anode in our experiments. © 2011 Canadian Society for Chemical Engineering

Enhanced coking resistance of Ni cermet anodes for solid oxide fuel cells based on methane on‐cell reforming by a redox‐stable double‐perovskite Sr 2 MoFeO 6‐δ

“…The superiority of SOFC over other fuel cells is fuel flexibility. Theoretically, all reductive fuels can be directly used as SOFC fuels, such as H 2 , carbonaceous species, H 2 S or NH 3, etc, which are oxidized by oxygen anion transferring from electrolyte. When H 2 is fed, Ni‐based cermets are commonly used as SOFC anode materials and have shown excellent performance because of its desirable catalytic activity towards H 2 electrochemical oxidation, good chemical and mechanical stability, low cost and so on.…”

A Fully Coupled Multiphysics Model for a H[sub 2]S SOFC

“…This is to be expected because as the H 2 content in the fuel is increased, the equilibrium dissociation of H 2 S goes down drastically. 12 The lower the equilibrium extent of reaction, the quicker the approach to equilibrium. Thus, the reaction is no longer kinetically controlled as it is close to equilibrium, as seen here for y H 2 ,in Ͼ 0.15.…”

Electrochemical Analysis of a System Based on W and Ni Combined with CeO2 as Potential Sulfur‐tolerant SOFC Anode

“…The open circuit values (OCV) measured after one hour of H 2 S exposure for each concentration were 1,037, 1,030, 1,028, 1,025, 1,022 and 1,043 mV for 0, 10, 50, 100, 300 and 500 ppm of H 2 S, respectively. It can be observed a decrease in the OCV values with an increasing H 2 S (0-300 ppm) except for 500 ppm H 2 S. It is well known that information about anode reactions can be obtained from OCV measurements but, unfortunately, the OCV interpretation becomes much more complex when a mixture of H 2 and H 2 S is fed to the cell; multiple reactions can take place at the anode [22,23]: the hydrogen oxidation (Eq. (1)), the partial oxidation of H 2 S to sulfur (Eq.…”