Changes in Oil Palm Frond Fiber Morphology, Cellulose Crystallinity and Chemical Functional Groups during Cellulose Extraction Phases

Abstract

Oil palm fronds (OPF) are agricultural by product and economical natural fibers resources. Cellulose is the main constituent in plant cell wall and because of its mechanical properties, cellulose fibers are potential to be utilized as reinforcement in composite product. The strength of cellulose is affected by its crystalline structure. To extract cellulose from natural fibers, lignin and hemicellulose have to be separated for instance by pulping and bleaching process. The main goal of this study was to observe changes in the OPF fibers morphology, cellulose crystallinity and chemical functional groups during cellulose extraction phases. Soda pulp of OPF was bleached using hydrogen peroxide. Subsequently, the bleached pulp was reacted with potassium hydroxide to eliminate hemicellulose. Afterward, further hydrogen peroxide bleaching was conducted to extract the cellulose. Surface morphological study using SEM revealed that there was a reduction in fiber diameter during cellulose extraction. Cellulose crystallinity and chemical functional groups at each phase of cellulose extraction were slightly different as demonstrated by XRD and FTIR analysis. Keywords: oil palm frond soda pulp, cellulose extraction, fiber morphology, cellulose crystallinit