Attempt of utilizing liquid fuels with Ni–ScSZ anode in SOFCs

Direct feeding of n-dodecane as model fuel for higher hydrocarbons was attempted using a cell of ScSZ electrolyte with Ni–ScSZ cermet anode at 1073 K. Direct feeding of n-dodecane using an evaporator at low steam to carbon ratios (S/C=0.05 to 0.1) led to immediate carbon deposition on the anode and, eventually, anode disintegration. When n-dodecane at S/C=2 was directly fed after bubbling Ar gases in water and in hydrocarbons, a continuous and stable operation was achieved; this was carried out for 120 h at a constant current density (38.21 mA/cm2) in the range from 0.7 to 0.8 V. Among carbons fed into the cell, CO (52.0%) and CO2 (4.4%) were formed, with the rest of carbons remaining as CH4 (8.8%) and other hydrocarbons because of low (15%) fuel utilization.