A fast adsorption of methylene blue by tobacco rob residues from aqueous solutions

Tobacco rob residues (TRR) were used as an adsorbent for the adsorption of methylene blue (MB) from aqueous solutions. The structure and morphology of the TRR were characterized by Fourier- transform infrared spectroscopy, X-ray diffraction, Zeta potential and N2adsorption–desorption. The effect of contact time, pH, tobacco rob residues dosage, sodium chloride (NaCl) concentration and initial concentration of MB were investigated by a series of static adsorption experiment. Meanwhile, the adsorption isotherms were determined and fitted by Langmuir and Freundlich adsorption isotherm. The results confirmed that the adsorption isotherm data fitted well to Langmuir isotherm with monolayer adsorption capacity of 233.3 mg/g. The adsorption processes were studied by pseudo-first order, pseudo-second order and intra-particle diffusion kinetic models. And the adsorption kinetics was found to follow a pseudo-second order kinetic model. TRR also have the advantages of facile recovery and recycle. Thus, TRR is potential to be used as a good natural adsorbent.