Synthesis and Use of Cellulosic Material for the Removal of Heavy Metals from Contaminated Wastewater

Abstract

Sawdust is a waste generated in large amount in the wood industry. In this study, the spent cellulose was extracted from wood sawdust which was obtained from the wood industry. The cellulose was then modified through iron salts (FeCl2.4H2O and FeCl3.6H2O) to increase the surface functional groups which are suitable for the adsorption process. The synthesized cellulose and magnetic cellulose were being characterized by the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analyses. Batch mode adsorption experiments were performed at neutral pH. It was observed that magnetically modified cellulose has a greater adsorption capacity to remediate Cd (II) ions from the aqueous solution. For contact time experiment, the adsorption capacity (qe) was 488.9 mg g-1 at 1 h whereas for the initial concentration experiment, the highest adsorption capacity (qe) was 1182.07 mg g-1 at 120 mg L-1 . The adsorptive kinetic experiments of Cd (II) adsorption showed that pseudo-second order was the best-fit model and demonstrated that chemisorption can be the predominant mechanism of adsorption of Cd (II) on magnetic cellulose. For adsorption isotherm experimental data, it was demonstrated that the Freundlich model was the best-fit isotherm with a significantly high adsorption capacity qmax (1547.8 mg g-1 ) by magnetic cellulose adsorbent. Overall, the results exhibited that the magnetic cellulose extracted from wood sawdust can be very useful and has very significant adsorption capacity in order to remove Cd (II) ions from an aqueous solution.