Pyrolysis behaviors of rice straw, rice husk, and corncob by TG-MS technique

The pyrolysis behaviors of rice straw, rice husk, and corncob have been investigated with the TG-MS technique, while paying close attention to the gas formation during the pyrolysis. The weight decreasing profiles and the gas formation rates were significantly different among the samples although their elemental compositions were almost the same. It was found that H2O is the main product formed for all the samples. The differences in the gas formation rates were found to be due to their differences in the composition of hemicellulose, cellulose, and lignin. There were significant interactions between cellulose and lignin during the pyrolysis. The interactions between cellulose and lignin during the pyrolysis contributed to a decrease in tar yields but an increase in char yields. From the gas formation data and FTIR analyses of the chars, it may be concluded that the suppression of tar formation during the pyrolysis of biomass was brought about by the cross-linking reactions between lignin and cellulose to form H2O and ester groups during the pyrolysis.