Poisoning of SOFC anodes by various fuel impurities

Fuel quality issues in stationary fuel cell systems.

“…Siloxanes in the fuel gas can lead to the formation and deposition of SiO 2 that can affect many components of the fuel cell system, such as heat exchangers, catalysts, and sensors [3,19,20]. Few studies have investigated the effect of siloxanes on fuel cells.…”

“…Few studies have investigated the effect of siloxanes on fuel cells. Haga et al [19] showed that 10 ppm of D5 resulted in total SOFC failure in 30 h at 1000°C. The degradation was almost immediate at 800°C.…”

“…Since siloxanes are of particular concern for fuel cell systems [3,19,20], a reasonable replacement period for the carbon would be either before dichloroethane breaks through (81 days) or just before the first siloxane, D4, breaks through (~165 days). Dichloroethane adds ~50% out of the total chlorine concentration (370 ppb), if that species is not captured by the bed (note that there are 2 chlorine atoms per molecule).…”

Highly Efficient Biomass Utilization with Solid Oxide Fuel Cell Technology

“…The concentration of H 2 S was less than 0.5 ppm. The concentrations of the other fuel impurities, CH 3 SH, Cl 2 , HCl, NH 3 and siloxane, were below the detection limits (2 ppb, 60 ppb, 0.4 ppm, 0.6 ppm and 10 ppb, respectively), indicating that this gas can be fed directly into a SOFC (Haga et al, 2008). In any case, 1 ppm level H 2 S contamination must be taken into account even after desulfurization treatment.…”

“…According to thermochemical calculations (Haga et al, 2008), sulfur compounds exist as H 2 S at SOFC operational temperatures in equilibrium. Here, in order to investigate the influence of a fuel impurity, 1 ppm H 2 S was mixed with simulated biogas mixture (CH 4 /CO 2 = 1.5) during the galvanostatic measurement under 200 mA cm -2 .…”