A Solid Oxide Fuel Cell Operating in Gradual Internal Reforming Conditions under Pure Dry Methane

Abstract

International audienceA planar solid oxide fuel cell (SOFC) was designed to be operated in gradual internal reforming conditions under pure dry methane. Stable operation was achieved for about 30 h. This result was obtained by deposition onto a Ni–yttria-stabilized zirconia cermet of a highly active and carbon-deposition-resistant catalyst layer consisting of Ir/CeO₂. The performances of this layer were first evaluated in situ at open-circuit voltage, and then the principle of gradual internal reforming associated with electrocatalytic dissociation was demonstrated. The best cell performances with CH₄/H₂O=1/4 were 0.1 A cm⁻² at 0.55 V (about 55 mW cm⁻²) at 1173 K

SOFC Long Term Operation in Pure Methane by Gradual Internal Reforming

“…These two basic principles summarized in Figure 1, were applied for the experimental demonstration and durability tests of anode supported cells operating in Gradual Internal Reforming of dry methane with electro-catalytic dissociation in two different layers. The advantages of Gradual Internal Reforming with the use of a catalytic layer (delocalisation of the endothermicity, no water or reforming gas in the fuel, no carbon deposition, performances and durability increase) were already reported (10). The catalytic layer has no electrical function, and the cermet has no catalytic role towards the hydrocarbon conversion.…”

“…Below 1/3, the system will not release enough steam to ensure itself complete conversion, and methane will diffuse into the cermet yielding fast coking. More details concerning this concept will be found in our previous work (7)(8)(9)(10)(11)(12). This simplified principle mechanism was applied here study and the faradaïc efficiency was first optimized in H 2 above 1/3 by adjusting the experimental parameters (fuel concentration and flow rates).…”

Direct Utilization of Liquid Fuels in SOFC for Portable Applications: Challenges for the Selection of Alternative Anodes

“…The presence of temperature gradients and coking are the main limitations for DIR-SOFC. Research on direct internal reforming SOFC with Ni/YSZ anode is limited almost exclusively to methane [17][18][19][20][21][22][23], with few examples of IIR-SOFC using model fuels [24][25][26].…”

Direct methane solid oxide fuel cell working by gradual internal steam reforming: Analysis of operation

“…Encouraging experimental tests have already been reported [11,12] for tubular and planar configurations. This paper provides an accurate characterisation of the middle-term operation of a fuel cell that presents this original architecture.…”