Chemical Modification of Cellulose Isolated from Underutilized Hibiscus sabdariffa via Surface Grafting: A Potential Bio-based Resource for Industrial Application

Abstract

Grafting of ethylenediamine onto Hibiscus sabdariffa cellulose was achieved via the simple reaction mechanism. The modified Hibiscus sabdariffa cellulose (HSM) and unmodified Hibiscus sabdariffa cellulose (HSC) were characterized using Fourier transformed infrared (FTIR) spectroscopy, elemental analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), particle size distribution, zeta potential, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Both HSM and HSC were also analysed for their water holding capacity, oil holding capacity, swelling capacity, and heavy metal adsorption capacity. The particle size distribution of HSC was found to be monomodal, while that of HSM was bimodal. HSM performed better than HSC in terms of oil adsorption capacity and metal adsorption capacity especially for Pb 2+ and Cd 2+ ions. HSM also performed better than some reported cellulosic materials found in literature. These properties exhibited by HSM present it as a potential resource in the food industry and in treatment of heavy metal contaminated water.