Sulfur poisoning in Ni-anode solid oxide fuel cells (SOFCs): Deactivation in single cells and a stack

Biogas Production from Local Biomass Feedstock in the Mekong Delta and Its Utilization for a Direct Internal Reforming Solid Oxide Fuel Cell

“…Figure 6 shows the voltage of the SOFCs in the direct feed of simulated biogas mixture (CH 4 /CO 2 = 1) at 800 • C with and without 9Ni/HT-PSC monitored during H 2 S poisoning under galvanostatic conditions at 0.2 A cm −2 . The result without 9Ni/HT-PSC (Shiratori and Sakamoto, 2016) supports the previous reports (Shiratori et al, 2008;Hagen et al, 2014;Papurello et al, 2016) that DIR-SOFCs are quite susceptible to fuel impurities (H 2 S), and their electrochemical performances rapidly deteriorate due to the chemisorption of sulfur species derived from H 2 S on the surface of the Ni particles used in the anode material, which blocks the active sites for methane reforming and electrochemical oxidation, leading to a large increase in anode overvoltage. The drastic cell voltage drop by the addition of 5 ppm H 2 S indicates the strong deactivation of dry reforming of methane (CH 4 + CO 2 → 2H 2 + 2CO) within the porous anode volume but not by the deactivation of electrochemical oxidation of H 2 and CO. Because the real biogas produced from Mixture-III had almost identical composition to that of the simulated biogas mixture (CH 4 /CO 2 = 1) except for the presence of 14 ppm H 2 S, in this study, 10 ppm H 2 S poisoning test was performed during the galvanostatic measurement at 0.2 A cm −2 in the direct feed of the simulated biogas.…”

Biogas Cleaning: Activated Carbon Regeneration for H2S Removal

“…Through anaerobic digestion, these kinds of plants produce biogas, which can be used as fuel for feeding fuel cells. However, one of the main drawbacks for high-temperature solid oxide fuel cell (SOFC) generators is their low tolerability towards contaminants present in biogas, since they have detrimental effects, mainly related to catalyst deactivation, carbon deposition and pore clogging [4][5][6][7][8][9][10][11][12][13]. A clean-up section is therefore mandatory before entering the fuel cell generator in order to remove the most dangerous contaminants [14][15][16][17][18].…”

Performance Factors and Sulfur Tolerance of Metal Supported Solid Oxide Fuel Cells with Nanostructured Ni:GDC Infiltrated Anodes

“…For conventional Ni:YSZ cermet anodes a linear relationship was found between the drop in power output and the sulfur surface coverage calculated using the Temkin isotherm. 30,31 A few interesting but somewhat peculiar conclusions can be made by inspection of the reported plots. First, it requires quite high sulfur coverages before any effect of sulfur can be observed θ s > 0.5 and secondly the anode will still be very active at θ s = 1.…”