Biomass & Bioenergy, Vol.91, 250-258, 2016
Electricity generation from corn cob char though a direct carbon solid oxide fuel cell
Solid oxide fuel cell (SOFC) is a potential technology for utilizing biomass to generate electricity with high conversion efficiency and low pollution. Investigations on biomass integrated gasification SOFC system show that gasifier is one of the high cost factors which impede the practical application of such systems. Direct carbon solid oxide fuel cell (DC-SOFC) may provide a cost effective option for electricity generation from biomass because it can operate directly using biochar as the fuel so that the gasification process can be avoided. In this paper, the feasibility of using corn cob char as the fuel of a DC-SOFC to generate electricity is investigated. Electrolyte-supported SOFCs, with yttrium stabilized zirconia (YSZ) as the electrolyte, cermet of silver and gadolinium-doped ceria (GDC) as the anode and the cathode, are prepared and tested with fixed bed corn cob char as fuel and static ambient air as oxidant. The maximum power output of a DC-SOFC operated on pure corn cob char is 204 mW cm(-2) at 800 degrees C and it achieves 270 mW cm(-2) when Fe of 5% mass fraction, as a catalyst of the Boudouard reaction, is loaded on the corn cob char. The discharging time of the cell with 0.5 g corn cob char operated at a constant current of 0.1 A lasts 17 h, representing a fuel conversion of 38%. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and Raman spectroscopy have been applied to characterize the char-based fuels. (C) 2016 Elsevier Ltd. All rights reserved.