Isolation and characterization of cellulose particles from groundnut (Arachis hypogaea) shell waste for sustainable reinforcement applications

Abstract

The use of agro-based waste materials is a growing trend in research. The production of value-added products from such waste material is gaining popularity within the sustainable materials concept. Our study used a modified organic acid hydrolysis technique to produce groundnut shell waste microcrystalline cellulose (GSW MCC). The extracted MCC was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis/derivative thermogravimetry (TGA/DTG), scanning electron microscopy, surface roughness analysis, and density and yield measurements. The crystallinity index of the MCC was determined to be 48.91 %, with a crystallite size of 25.68 nm, ensuring consistency in reported values. The UV absorption peak was obtained at 283.82 nm. The highest thermal degradation and impurities were identified using TGA and DTG analysis. The particle size of the MCC was measured using ImageJ software. The scanning electron microscopy (SEM) analysis revealed a minimal roughness and a fibrous structure of MCC rather than showing distinct particles. The surface roughness analysis showed that the MCC possesses adequate surface roughness for filler applications. According to the atomic force microscopy study, GSW cellulose has a range of surface roughness, including sharp peaks and deep valleys, which suggests improved mechanical bonding and adhesion in composites. Comparative analysis with commercial MCC and literature data highlights the unique properties of the extracted MCC. The MCC obtained from GSW exhibits better physicochemical properties and can be used as a low-cost excipient in the manufacturing of pharmaceutical dosage forms and fillers in biocomposites.

Keywords: Agro-waste use; Arachis hypogaea; Biofiller; Biomass; Groundnut shell; Microcrystalline cellulose.