Adsorption Behavior of Reactive Dye from Aqueous Phase on Activated Carbon

摘要

The adsorption of a reactive dye (Procion Red) from aqueous solution onto activated carbon was investigated. The effect of contact time, pH, adsorbent dosage and temperature were studied. The equilibrium data were described well by both Langmuir and Freundlich isotherm model. The adsorption kinetics was tested for pseudo-first-order, pseudo-second order, intraparticle diffusion and unified approach kinetic models. The unified approach model described the kinetic data in accordance with the experimental data and the forward and backward rate constants were evaluated from the model fittings. The adsorption is highly pH dependent and adsorption efficiency increases with the decrease in pH. Thermodynamic parameters of the adsorption process suggested that the process was endothermic. The adsorption capacity of regenerated activated carbon showed more than 70% recovery of the adsorption efficiency of the initial virgin adsorbent.