Evaluation of thermodynamic parameters of 2,4-dichlorophenoxyacetic acid (2,4-D) adsorption

Thermodynamic parameters of 2,4-dichlorophenoxyacetic acid (2,4-d) adsorption were evaluated by studying the adsorption equilibrium and kinetics of 2,4-d at different temperatures. uptake capacity of activated carbon increases with temperature. langmuir isotherm models were applied to experimental data of 2,4-d adsorption. equilibrium data fitted very well to the langmuir equilibrium model. adsorbent monolayer capacity q0,langmuir constant a and adsorption rate constant ka were evaluated at different temperatures for activated carbon adsorption. the activation energy of adsorption (ea) was determined using the arrhenius equation. using the thermodynamic equilibrium coefficients obtained at different temperatures,the thermodynamic constants of adsorption (δg0,δh0,and δs 0) were evaluated. the obtained values of thermodynamic parameters show that the adsorption of 2,4-d is an endothermic process. © 2013 a. s. ghatbandhe et al.