Nanofibrillation and characterization of sugarcane bagasse agro-waste using water-based steam explosion and high-pressure homogenization

Abstract

Sugarcane bagasse waste, consisting of approximately 40–50% cellulose, has been widely used in a number of industries. The extraction and defibrillation of nanometer-scale cellulose fibers from such waste using strong chemical solutions have been extensively investigated. However, the using of strong chemical solutions can cause adverse effects to the fibers as well as negatively affect the environment. Some evidence has shown that mechanical treatments, such as steam explosion and high-pressure homogenization, are environmentally friendly when compared with chemical treatment techniques. This work aimed to isolate the cellulose nanofibers from sugarcane bagasse waste using steam explosion pretreatment at various temperatures (195, 200, 205, and 210 °C) and durations (5, 10, and 15 min) before passing through a microfluidizer within 12 passes of 200 mL cellulose suspension. The mean separation analysis using Duncan’s Multiple Range test showed that higher temperatures significantly improved the efficiency of non-cellulosic substances reduction, as evidenced by an increment of whiteness index (81.39–90.02), thermal degradation temperature (313.92–326.34 °C) and crystallinity index (74.27–81.42%). The obtained cellulose nanofibers exhibited very fine diameter within the range of 3–7 nm, had a high cellulose content (92.74 ± 0.14%) and a low density (0.8989 g/cm3). The obtained cellulose nanofibers could be applied in various fields such as medical, cosmetic, food packaging, and electronic device applications.