The Effect of Alkali Treatment on the Cellulose Extracted from Rice Husk as Potential Resources of Biomass

Over the last few decades, the use of agro by-products as a biopolymer for various applications has attracted significant interest of researchers. Rice husk (RH) is one of the agro by-products produced abundantly worldwide and a great deal of studies in extracting and utilizing silica from RH have been reported but scarcely for its cellulose components. A specific study on the utilization of cellulose extracted from RH for the electrospinning process also remains unreported. Chemical pre-treatment seems to be the most crucial step which improves the elimination of the cementing components and exposing the cellulose for further applications. This study aimed to explore the potential of RH as a source of raw material to produce cellulose nanofiber. The cellulose was extracted by acid pre-treatment, alkaline treatment at varying sodium hydroxide (NaOH) concentrations, followed by bleaching treatment with sodium hypochlorite for complete removal of the amorphous region. The resulting cellulose was characterized and the main properties (morphology and sizes) of the extracted cellulose were made using scanning electron microscopy (SEM). The findings revealed the almost complete removal of the noncellulosic components for the subsequent production of electrospun cellulose nanofibers. Therefore, the output of the cellulose from this underutilized agro-waste has commercial application potential that can add value and be further utilized for the electrospinning process.