Equilibrium and Kinetic Parameters Determination of Cr(VI) Adsorption by Hogla Leaves (Typha elephantina Roxb.)

Equilibrium and kinetic parameters of Cr(VI) adsorption on Hogla leaves (Typha elephantina Roxb.) were determined in a batch process. Batch adsorption experiments were carried out as a function of pH, adsorbent dosage and initial metal ion concentration. Maximum metal adsorption was found to occur at pH 2.0. The adsorption capacity of studied adsorbent was found to be 30.616 mg/g for initial Cr(VI) concentration of 400 ppm and optimum adsorbent dose of 10 g/L at 25°C. Compared to the Freundlich isotherm model, the Langmuir and Temkin model best fit the experimental data (R2>0.995). Batch adsorption models, based on the assumption of the pseudo firstorder and pseudo second order mechanism were applied to examine the kinetics of the adsorption. The results of this study demonstrated that the pseudo-second order model was more suitable than pseudo-first order model for adsorption of Cr(VI) by Hogla leaves. At 25°C, with a contact time of 360 minutes and agitation rate of 180 rpm, the potential of Cr(VI) removal by Hogla leaves from industrial effluent was also investigated at optimized condition of pH 2.0, initial metal ion concentration of 400 ppm and adsorbent dose of 10 g/L and removal efficiency was found to be 44.8%.