Comparative physicochemical characterization of cellulose extracted from Napier grass, bamboo, oil palm fronds, and empty fruit bunches

This paper investigates and compares various cellulose extraction methods applied to different raw materials, including Napier grass, bamboo, oil palm empty fruit bunches (OPEFB), and oil palm fronds (OPF). The study employed distinct sample preparation and cellulose extraction techniques. FTIR analysis revealed that almost all lignin and most hemicellulose were eliminated after chemical treatment. XRD analysis showed that cellulose samples extracted from bamboo and OPF exhibited the highest crystallinity index, around 61–62 %, compared to Napier stems and OPEFB, which had lower crystallinity, around 51–59 %. Nevertheless, all methods produced cellulose with crystallinity above 50 %, regardless of the raw materials or extraction techniques. Additionally, SEM analysis of raw and treated bamboo was performed to investigate morphology before and after the extraction process. This analysis revealed that the irregular structure of bamboo transformed into fibril bundles associated with cellulose fibers following chemical treatment. ANOVA results confirm that feedstock type significantly affects cellulose yield (P = 0.0016, F = 11.14), with 83.19 % of its variability explained by the model (R² = 0.8319). In contrast, its effect on the crystallinity index is moderate (F = 3.54, P = 0.0535), explaining 61.11 % of the variation (R² = 0.6111). This study provides insights into extracting high-crystallinity cellulose while minimizing chemical usage, reducing waste, and improving adaptability across biomass sources for sustainable industrial and environmental applications.