Adsorption Characteristics of Phosphate in Residual Dredging Water by Zeolite Modified with Magnetic Zirconium/Iron

Zeolite modified with magnetic zirconium/iron was prepared by coprecipitation method. Based on exploring its adsorption characteristics of phosphate in residual dredging water, the phosphate adsorption characteristics were determined through characterization of its structure by XRD. The adsorption characteristics of the phosphate in the residual dredging water by the zeolite modified with magnetic zirconium/iron could be described by Langmuir isothermal adsorption model, quasi- secondary kinetic model and particle internal diffusion model. When the adsorbent dosage was 18 mg/L and the pH was 7, the maximum adsorption capacity of phosphate in the residual dredging water was 11.4 mg/g (calculated as phosphorus). When the pH was between 5 and 7, the adsorption efficiency of the zeolite modified with magnetic zironium/iron on phosphate was better, and the adsorption amount decreased obviously under alkaline condition. When the temperature was between 10 ℃ and 30 ℃, the adsorption efficiency of phosphate increased with the increase of temperature. The adsorption of phosphate in water by the zeolite modified with magnetic zirconium/iron belonged to chemical adsorption.