ADSORPTION OF PHOSPHORUS ON DIFFERENT SEDIMENTS

Experiments were performed to investigate the adsorption behaviors of phosphorus on different sediments. Two kinds of sediment from Yangtse River were selected, one of which is silt with D <= 0.062mm and the other is sand with 0.062mm <= D <= 0.25mm. The effects of initial concentration of phosphorus and sediment content on the adsorption of phosphorus were studied. As the initial concentration of phosphorus increased, both the total and unit amount of phosphorus adsorbed by sediments increased, the adsorption proportion of phosphorus decreased; However, as the sediment content increased, both the total adsorbed amount and the adsorption proportion of phosphorus by sediments increased, the unit adsorbed amount decreased; Under the same experiment condition, the adsorbed amount of phosphorus by silt was more than by sand obviously. The adsorption behavior of phosphorus on silt accorded with the isothermal adsorption isotherms better than on sand; On the same kind of sediment, the adsorption behavior of phosphorus accorded with Freundlich adsorption isotherm better than Langmuir adsorption isotherm.