Preparation of wood sawdust/Fe2O3 nanocomposite and its application for arsenic (III) ion removal from aqueous solutions

Abstract

This paper describes the potential use of α-Fe2O3 nanoparticles (α-Fe2O3 NPs) and α-Fe2O3 sawdust nanocomposite (α-Fe2O3/SD NC) toward the removal of arsenic from aqueous systems. The α-Fe2O3NPs were synthesized by the co-precipitation method on sawdust. The samples were characterized using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). SEM micrographs showed the formation of α-Fe2O3NPs within 40-60 nm in size, which were homogeneously dispersed on the sawdust surface. The adsorption experiments were performed in a batch system. The optimum pH value for the maximum removal of As(III) was found at a value of about 7. The monolayer adsorption amounts calculated based on the Langmuir adsorption model were 83.33 and 58.80 mgg-1 for α-Fe2O3 and α-Fe2O3/SD, respectively. The kinetic data obeyed the pseudo-second-order kinetic model. The high adsorption capacity was attributed to the high surface area of α-Fe2O3NPs and good dispersion α-Fe2O3NPs on the sawdust substrate. The experimental results suggest that α-Fe2O3/SDNC is a promising and cost-effective adsorbent for the removal of As(III) ions from aqueous solutions. © 2018 Editura Academiei Romane. All rights reserved.