Removal of Hazardous Indigo Carmine Dye from Waste Water Using Treated Red Mud

The present work aims at developing an effective technologies in treating such effluents from Indigo Carmine (IC) dye industry through the use of the industrial wastes such as red mud. Red mud, hazardous aluminium industry waste in its activated form using hydrazine sulphate is employed in the removal of the IC dye by batch adsorption operation. The adsorbent is characterized by FESEM, EDX and FTIR methods and found to be potent enough in up-taking the IC dye. However, sensitivity analysis is carried out in identifying the optimum operating conditions at which the ultimate the adsorption capacity of the red mud is found to be 62.6 mg/g with 94.0% overall removal of the IC dye. The adsorption mechanism is analysed by various adsorption isotherm models and the kinetics of the adsorption process is examined. Further, the thermodynamic investigation projected the operation to be spontaneous and endothermic. Regeneration studies indicated the recyclability of the developed adsorbent with % removals not falling below 85.0% even after five regenerations cycles. However, the adsorbent is tested for its reliability by applying it to the water effluents gathered from commercial IC dye polluting industry and found effective enough in its use as a potential adsorbent in water treatment operations. (C) 2019 Elsevier Ltd. All rights reserved.