Performance improvement of direct internal reforming solid oxide fuel cell fuelled by H2S-contaminated biogas with paper-structured catalyst technology

Abstract

Direct internal reforming (DIR) operation of a solid oxide fuel cell (SOFC) is a very attractive concept for downsizing and cost reduction of SOFC systems. This study aimed to develop stable operation of a DIR-SOFC fuelled by biogas. The current-voltage (I-V) curves of 2 x 2 cm 2 planar SOFCs (anode-and electrolyte-supported cells, ASC and ESC, respectively.) were measured at 800 °C in the direct feed of a simulated biogas mixture (CH4/CO2 = 1), and the flexible structured catalyst material (paper-structured catalyst (PSC)) was applied on the anode material for performance enhancement. By applying a hydrotalcite (HT)-dispersed PSC (HT-PSC), the sulfur tolerance of the SOFC in the DIR operation was remarkably improved. By the effect of the HT-PSC, for both ASC and ESC, a stable cell voltage higher than 800 mV was obtained over 200 h at 0.2 A cm-2 in the direct feed of simulated biogas under 5 ppm H2S poisoning.

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

“…Pt wires welded with Pt mesh were applied to the anode and cathode as voltage and current-collecting probes. Frontiers in Environmental Science | www.frontiersin.orgFIGURE 3 | Photographs of (A) SOFC single cell (electrolyte-supported cell) and (B) Ni-loaded hydrotalcite-dispersed PSC (9Ni/HT-PSC) (Shiratori and Sakamoto, 2016). Real biogas stored in a polymer bag was supplied to the PSC/SOFC stack using an aspiration pump (C).…”

“…As shown in Figure 3B, 9 wt% Ni-loaded hydrotalcite ([Mg 6 Al 2 (OH) 16 CO 3 ]4H 2 O, HT)-dispersed PSC (9Ni/HT-PSC) was prepared by a papermaking technique using a dual polyelectrolyte retention system and subsequent impregnation and sintering processes (Shiratori et al, 2015;Shiratori and Sakamoto, 2016). The microstructure of the prepared 9Ni/HT-PSC is shown elsewhere (Shiratori and Sakamoto, 2016).…”

“…The microstructure of the prepared 9Ni/HT-PSC is shown elsewhere (Shiratori and Sakamoto, 2016). Ceramic fiber (SiO 2 : 52 wt%, Al 2 O 3 : 48 wt%) was welded using a yttria stabilized zirconia (YSZ) sol to form an inorganic fiber network with an average size of macropores and porosity of 16 µm and 89%, respectively.…”

“…An attractive feature of the present biogas is its very low H 2 S concentration of 9.0, 14 and 51 ppm for Mixture-II, III and IV, respectively, in comparison to general biogas containing 500-4,000 ppm (Alves et al, 2013). Using SOFC technology, the real biogas produced in this study is considered to be converted directly into electricity without any fuel processing, provided that PSC is applied on the anode material (Shiratori and Sakamoto, 2016). 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 .…”

“…This is the first report using methanogenic bacteria in the shrimp pond sludge for the digestion of bagasse and molasses. Furthermore, the produced biogas was used as fuel for the test on SOFC in which direct internal reforming (DIR) technology (Staniforth and Kendall, 1998;Yentekakis, 2006;Janardhanan et al, 2007;Shiratori et al, 2008;Lanzini and Leone, 2010;Leone et al, 2012;Papadam et al, 2012;Lanzini et al, 2013) using a paper-structured catalyst (PSC; Fukahori et al, 2006;Shiratori et al, 2015;Shiratori and Sakamoto, 2016) was applied to achieve SOFC power generation by direct feed of the biogas without any fuel processing.…”