Magnetic nanocomposite of activated charcoal for removal of Congo red dye Equilibrium and kinetic modeling

Purpose - The purpose of this paper is to focus on the removal of Congo red dye from aqueous solution using magnetically separable novel adsorbent prepared by coating activated charcoal on magnetic nanoparticles. Design/methodology/approach - The synthesized magnetic nanocomposite of activated charcoal was characterized using Fourier transform infra-red (FTIR), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) analysis. The removal of Congo red from aqueous solution using magnetic nanocomposite of activated charcoal was optimized. The equilibrium and kinetics modeling of adsorption of Congo red was analyzed. Findings - The presence of activated charcoal on magnetic nanocomposite was confirmed by FTIR analysis. The average size of the nanocomposite was found to be 12.77 nm using SEM characterization. The elemental composition by EDS analysis confirmed the increase in concentration of carbon due the adsorption of Congo red dye. The optimum conditions for batch adsorption was found to be 1 g/L of adsorbent, dye concentration 50 mg/L, pH 3 and temperature 70 degrees C. The adsorption of Congo red dye on magnetic nanocomposite of activated charcoal was found to follow Temkin adsorption isotherm. Originality/value - The experimental data were found to fit well with the pseudo second-order kinetics and the rate of adsorption was found to be controlled by intra-particle diffusion.