Biosorption of Cr(VI) ions from aqueous solutions: Kinetics, equilibrium, thermodynamics and desorption studies

► Six different natural adsorbents used for the removal of Cr(VI) from aqueous solution. ► The kinetic data were better fitted by pseudo second order model. ► Adsorption process was jointly controlled by film diffusion and intraparticle diffusion. ► D-R isotherm and thermodynamic study indicated that the process was chemical in nature. ► Functional groups responsible for the adsorption process were indentified by FT-IR analysis. ► Application study using electroplating unit effluent indicated the applicability of natural adsorbents.