Determination of chemical composition and structural changes of torrified oil palm fronds (OPF) pellets via TAPPI method/ FTIR

Torrefaction is a mild thermolysis process, which efficiently convert energy and biomass homogenization that involves in an inert atmosphere and low temperature of 200 to 300°C for about 60 minutes at atmospheric pressure. The basic principle of torrefaction involves the process of removing oxygen and hydrogen and also the enhancement of carbon as the final product. This pretreatment helps in reducing moisture content, atomic O/C and H/C ratioS and it also help to boost the heating value, hydrophobicity, grindability, flowability and homogeneity of the biomass. In this research, an agricultural waste from oil palm plantation, oil palm frond (OPF) is subjected to the pretreatment process of torrefaction in a horizontal tube furnace at five temperatures and holding time of 60 minutes. Biomass compositional results and Fourier Transform Infrared Spectrometer (FTIR) analysis of OPF were compared within five temperatures. Results acquired revealed that the highest percentage in extractives, cellulose and hemicellulose was found in raw OPF compared to other torrefied OPF showing that torrefaction process were successful to reduce these composition at the end of this study. Meanwhile, the highest percentage of lignin was at 300°C as lignin was the hardest composition to be thermally degraded due to its ability to decompose in a much wider temperature range and known to have stronger chemical bonds. From FTIR analysis, it was concluded that the structure of hemicellulose and lignin were greatly affected by torrefaction whereas the structure of cellulose were affected slightly. Therefore, result gained proved that torrefaction is a great alternative in converting raw biomass into a promising renewable energy.