KINETICS, THERMODYNAMICS AND ISOTHERM MODELING OF ADSORPTION OF TRIPHENYLMETHANE DYES (METHYL VIOLET, MALACHITE GREEN AND MAGENTA II) ON TO FRUIT WASTE

Batch experiments are carried out for the sorption of Methyl violet(MV), Malachite green(MG) and Magenta II onto fruit waste. The operating variables studied are initial dye concentration, contact time, adsorbent dose, pH and temperature. The equilibrium data are fitted to the Langmuir and Freundlich isotherm equations. From these the adsorption efficiency, adsorption energy, adsorption capacity, intensity of adsorption and dimensionless separation factor are calculated. The experimental data fitted very well with pseudo second order kinetic model and intraparticle diffusion models. The adsorp-tion of dyes increased with increase in temperature from 302K to 322K, indicating the process to be endothermic. The thermodynamic parameters like G0, H0 and S0 all are calculated from the studies on effect of temperature. Desorption studies show that adsorption of MV, MG, and Magenta II is chemisorpic.