Effect of Chemical Treatment Sequence on Pineapple Peel Fiber: Chemical Composition, Thermal Stability and Thermal Degradation Kinetics

Millions of tons of fruit wastes are generated globally every year from residual agriculture, which makes essential to find alternative uses to increase their aggregate value and reduce the impact of environmental damage. The present study aimed to explore pineapple peel as an alternative source of cellulose by evaluating its composition and physical properties, which are essential to provide a clue to its application function diverse. Cellulose was extracted by a sequence of chlorine-free treatments to delignify the fresh pineapple peels, followed by characterization using chemical composition, XRD, FTIR, SEM and TGA to determine its crystallinity, structural properties, morphology thermal characteristics, and thermal degradation kinetic study. The result revealed that the pineapple peel amorphous segments containing hemicelluloses and lignin were extensively removed with increasing chemical treatments, leading to increased purity, crystallinity index and thermal stability of the extracted materials. The maximum degradation, and crystallinity index of the 2B isolated from the PPF are 150 °C and 80.91% respectively. The cellulose content increased from 24.05% (pineapple peel) to 80.91% (bleached cellulose). These results indicated that pretreatment via bleaching has suitable potential applications in nanocrystal production and suggests possible uses in the development of cellulose nanocrystal and application for packaging films.