EFFECT OF START-STOP CYCLE AND IRON DOPING ON HYDROGEN SOLID OXIDE FUEL CELL PERFORMANCE AND SIMULATION OF NATURAL GAS FUEL

• Main Author: Shofi Rachmadita, Dhea
• Format: Theses
• Language: Indonesia
• Subjects: Teknik kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/54730
• Institution: Institut Teknologi Bandung

Durability of SOFC need to be tested with influence of start-stop cycle. Performance of hydrogen fuel cell tested at 800°C then hydrogen supply stopped and the temperature was set to room temperature. Cell off for 10 hours then performance of the cell tested at 800°C. This cycle operation was carried out for three times. After first cycle, voltage and maximum power density of the cell decreased from 0,28 V and 0,22 mW/cm2 to 0,13 V and 0,02 mW/cm2. After second cycle, voltage and maximum power density increased to 0,31 V and 0,03 mW/cm2. After third cycle, performance of the cell stable at voltage 0,23 V and maximum power density 0,03 mW/cm2. Dense or low porosity of SOFC’s electrolyte need to be achieved in order to prevent hydrogen crossover to cathode or air to anode. Calcia-stabilized zirconia (CSZ) electrolyte which sintered at 1100°C for 2 hours had high porosity due to low sintering temperature. Increasing sintering temperature will lower the porosity but need higher energy. Therefore, doping was used to lower the activation energy of sintering. In this research work, calcia-stabilized zirconia (CSZ) electrolyte was doped with iron powder. The Fe sources used were Fe2O3 dan Fe(NO3)3.9H2O. Fe doping from both sources decreased electrolyte resistivity and increased electrolyte density. Cell with CSZ-Fe2O3 electrolyte had higher voltage and maximum power density (0,37 V and 0,49 mW/cm2) than cell without Fe doping (0,28 V and 0,22 mW/cm2). Performance of SOFC from experiment modelled in order to simulate using natural gas fuel. Increasing steam to carbon ratio decreased the voltage of natural gas fuel cell. Performance of natural gas fuel cell lower (0,21 V and 0,1 mW/cm2) than hydrogen fuel cell (0,37 V and 0,5 mW/cm2).