Abstract

Excessive toxic metals are commonly found inpolluted water bodies. This study aimed to synthesisekenaf-based adsorbents for the adsorption of lead (II) ions. Thephysical and chemical characteristics of the kenaf (KNF) coreand fibre were determined using field emission scanningelectron microscope (FESEM), thermogravimetric analysis(TGA), and Fourier-transform infrared spectroscopy (FTIR).The further synthesised kenaf-chitosan-alginate(KNF-CHT-ALG) beads were characterised through FESEMand FTIR, while inductively coupled plasma (ICP) wasemployed to determine the percentage of adsorption. TheFESEM analysis demonstrated that the KNF core had arougher surface morphology than the KNF fibre. The TGAanalysis confirmed that the KNF core was coarser andcontained a higher residue of approximately 75.91%. The FTIRspectra established intense functional groups in the KNF core,such as hydroxyl and carboxyl, attracting more Pb (II) ions.The KNF core was then used to synthesise KNF-CHT-ALGbeads. The beads confirmed the enhancement in surfacemorphology and the existence of numerous functional groupsfor Pb (II) ions to bind. The ICP analysis demonstrated 95% ofPb (II) ion adsorption. Additionally, batch adsorptionexperiments were conducted at pH 2–7 and the contact time waswithin 5–60 minutes. The kinetic study of the adsorptionfollowed the pseudo-second order model with an R2 value of0.9999. The KNF is a crop found in abundance in Malaysia,which could reduce the production cost of adsorbents. Thesignificant outcomes would minimise the dependency onchemical adsorbents and accelerate the removal process ofheavy metals in natural bodies of water.