Abstract: Using FeCl₃·6H₂O，FeCl₂·4H₂O and NaOH as raw materials, the magnetic fluid Fe₃O₄ was prepared firstly, and then sodium dodecyl benzene sulfonate (SDBS) modified sodium alginate (SA) magnetic spheres were prepared.  The effects of pH value, initial mass concentration, adsorption time and temperature on the adsorption of Cu²⁺ in the water were investigated by single factor experiment, the coordination characteristics of SA anion and Ca²⁺ and Cu²⁺ were simulated at the level of B3LYP/6-31G^**. The results show that at 25 ℃, the adsorption time is 80 min, the mass concentration of Cu²⁺ is 100 mg/L and pH=4, the maximum adsorption amount is 116.6 mg/g, and the bonding ability of Cu²⁺ is stronger than that of Ca²⁺.

Key words: sodium alginate magnetic sphere, static adsorption, dynamic simulation