Effect of Combining Chemical and Irradiation Pretreatment Process to Characteristic of Oil Palm's Empty Fruit Bunches as Raw Material for Second Generation Bioethanol

Oil palm's empty fruit bunches (OPEFB) as the waste from oil palm industry is one of lignocellulosic biomass feedstocks for a potential second-generation bioethanol production. Pretreatment process is a key processfor producing bioethanol. OPEFB treated is expected to give better properties used for bioethanol production. This research aims to study the effect of pretreatment process by combining chemical and irradiation to OPEFB's properties as raw materials in the hydrolysis reaction producing sugars which will be fermented into ethanol. The raw materials are characterized in term of crystallinity, chemical structure, chemical content, and surface morphology. Analysis results of chemical content showed that cellulose and hemicellulose content increased significantly while lignin content decreased significantly after pretreatment. The crystallinitymeasured byX-Ray Diffraction (XRD) showed that after pretreatment, their crystallinity indexand the crystallite size increased significantly. While, the surface morphology and composition shown by Scanning Electron Microscope/EnergyDispersive X-ray spectroscopy (SEM/EDX) showed the changing in morphology surface and dominantly composed by carbon and oxygen.