Abstract: | Treated red mud, the solid residue from bauxite processing, was found to adsorb phosphorus from dilute aqueous solution effectively. Experiments were carried out in aqueous as well as buffer media to obtain the optimum conditions like contact time, pH, adsorbent dose, adsorbate concentration, temperature etc. The pH value of 4.5 was found to be optimum for maximum removal. The equilibrium was attained within 60 mins. Lower adsorbent dose and higher initial phosphorus concentration favoured higher loading capacity. The adsorption process followed Freundlich isotherm and Lagergren equations and they followed first order rate kinetics. The effect of different anions on phosphorus removal could be explained on the basis of the changing affinity of anions for the surface and their relative concentrations. |