Adsorption Study for the Treatment of Wastewater Using Cloisite 15A as an Adsorbent

Abstract

Textile industries consume large amount of water. It produces highly coloured wastewater. The quality of water is greatly influenced by the color. Textile wastewater needs proper treatment before discharged into the environment. Textile dyes are toxic, carcinogenic in nature and this causes a serious problem to living organisms. Adsorption study was conducted for the removal of Reactive Black 5 onto Cloisite 15A. Adsorption of RB5 was highly affected by contact time, pH, adsorbent dosage and initial dye concentration. The adsorbent dosage study was contacted by taking C0 = 100 mg/l at natural pH and T = 303 K. The pH study was carried out in the initial pH range (pHi) of 3 to 11 at 303K with optimum adsorbent dosage (0.35g/l). HCl or NaOH was used to adjust the pH of RB5 solution. To study the effect of time the equilibrium experiments were performed at various dye concentration (C0 = 50 to 300 mg/l), mad= 0.35 g/l and at optimum pHopts. Pseudo first order and second order model were used to study the kinetic models. It was found that all the experimental data fitted well in the second order kinetic model. Three equilibrium isotherms were analyzed: Langmuir, Freundlich and Temkin isotherm. The isothermal experiments were performed at different C0 values ranges from 50 to 300 mg/L with optimum adsorbent dosage and at optimum pH and the result shows that the process is endothermic in nature. Characterization was done by using XRD and TEM techniques.