Microwave-enhanced CO2 gasification of oil palm shell char

• Microwave heating system was developed to convert CO2 to CO via Boudouard reaction.
• Superior performance of microwave over thermal driven gasification was observed.
• Formation of hot spot in microwave heating pronouncedly improved char reactivity.
• Ea of 74 and 247 kJ/mol was obtained for microwave and thermal CO2 char gasification.
• CO2 conversion of 99% was achieved in microwave gasification of Fe-catalyzed char.

CO2 gasification of oil palm shell (OPS) char to produce CO through the Boudouard reaction (C + CO2 ↔ 2CO) was investigated under microwave irradiation. A microwave heating system was developed to carry out the CO2 gasification in a packed bed of OPS char. The influence of char particle size, temperature and gas flow rate on CO2 conversion and CO evolution was considered. It was attempted to improve the reactivity of OPS char in gasification reaction through incorporation of Fe catalyst into the char skeleton. Very promising results were achieved in our experiments, where a CO2 conversion of 99% could be maintained during 60 min microwave-induced gasification of iron-catalyzed char. When similar gasification experiments were performed in conventional electric furnace, the superior performance of microwave over thermal driven reaction was elucidated. The activation energies of 36.0, 74.2 and 247.2 kJ/mol were obtained for catalytic and non-catalytic microwave and thermal heating, respectively.

Figure optionsDownload as PowerPoint slide