▎ 摘　　要

Chromium released with tannery effluent causes severe water pollution which is a great concern to the environment and public health. Removal of chromium from tannery effluent prior to discharging to the surface water is a crying need for protecting environment and human health. This article describes the preparation and characterization of graphene oxide (GO) and its adsorption potential for Cr(III) from hazardous chrome-tanning effluents. GO was characterized by X-ray diffraction analysis, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and Zeta potential measurement. Explanation of the adsorption mechanism, kinetics, and feasibility were also studied. The influence of different operational variables, for example, pH, adsorbent dosage, Cr(III) ion concentration, contact time, and temperature on adsorption of Cr(III) on GO were evaluated by batch experiments. Adsorption equilibrium of Cr(III) data matched with both Langmuir and Freundlich isotherms and the maximum adsorption capacity (q(m)) was calculated from Langmuir isotherm and found as 366.3 mg/g. Cr(III) and other pollutants removal efficiency of GO was studied for the real effluent sample having Cr(III) concentration of 3,477.5 mg/L. At a GO dosage of 1.0 g/100 mL 51.88% Cr(III) was removed in just 20 min of treatment, while biochemical oxygen demand, chemical oxygen demand, and total dissolved solids removal was 57.93%, 55.41%, and 61.4%, respectively. The adsorption kinetics fitted well with a pseudo-second-order reaction model and thermodynamically it was spontaneous at lower temperature and exothermic in nature. Cr(III) loaded adsorbent was regenerated and reused for further adsorption.