Kinetics torrefaction of emptry fruit bunch (EFB), mesocarp fiber and kernel shell of oil palm

Torrefaction is a thermal pretreatment process to pretreat biomass at temperature range within 200-300oC under an inert atmosphere. In this study, oil palm wastes i.e. empty fruit bunch (EFB), palm mesocarp fiber (PMF) and palm kernel shell (PKS) were torrefied in thermogravimetric analyzer (TGA). The data obtained from TGA was used to create kinetic model which to predict amount of torrefied solid. A two-step reaction mechanism was suggested; the fast initial step was hemicellulose decomposition while slower second step was charring of hemicellulose fractions. The hemicellulose decomposition was more significant than cellulose and lignin during torrefaction because its temperature decomposition between 225-325°C. Based on experimental and model curves, weight loss for EFB and PMF were higher than PKS. It was because they composed higher hemicellulose content compared to PKS. In contrast, PKS contained higher lignin content than EFB and PMF which make it more difficult to decompose.