Behavior of anode-supported SOFCs under simulated syngases

Abstract

The carbon amounts of simulated syngases with different compositions were calculated in this study. The degradation and carbon deposition behavior of solid oxide fuel cells (SOFCs) with an active area of 4 cm × 4 cm were then investigated under the simulated syngases at work conditions. Carbon deposition occurred over time with a little or no H2O and CO2 in these gasses, which significantly degraded the single cells. The cell stabilized within 1 h under a gas mixture of 70 % H2–30 % CO because of the chocking of inlet pipelines of the testing house by carbon deposition. Addition of proper H2O and CO2 in the simulated syngas effectively suppressed carbon deposition in the pipelines. However, carbon was still deposited gradually in the single cell anode when H2O and CO2 were insufficient. The mechanisms of carbon deposition were different when the cells were exposed under different syngases. Single cells steadily thrived under 50 % H2–20 % CO–10 % CO2–20 % H2O and 50 % H2–20 % CO–20 % CO2–10 % H2O gas mixtures for about 2000 h without carbon deposition.