Synthesizing and evaluating adsorption kinetics of removing Congo Red dyes onto exfoliated graphite

Abstract

Exfoliated graphite was synthesized by thermal microwave – assisted method. Here, we reported the facile synthesis and characterization of chemical bonds of EG using several techniques such as X-ray Power Diffraction Spectroscopy (XRD), Fourier-transform infrared spectroscopy (FT-IR), and and N2 adsorption/desorption isotherm mesurement. The result of XRD analysis showed peak intensity, proving the high crystallinity of EG, which is suitable with the FT-IR analysis. The specific surface area and pore volume of EG achieved were 40.95 m2/g and 0.16176 cm3/g, respectively. To elucidate the adsorption kinetic of CR over EG adsorbents, kinetic models including: pseudo first-order, pseudo second-order, Elovich, and Bangham models have been adopted. The kinetic results indicated that models adhered to the pseudo second-order equation with high coefficients R2 > 0.98.