铈改性净水污泥除磷效能与机理分析OA北大核心CSTPCD

Phosphate content is one of the important criteria for controlling the quality of the water environment,and adsorption is an efficient,clean,and economical technique for phosphate removal.In this study,cerium-modified drinking water treatment residual was used to remove phosphate by adsorption,and the effects of cerium loading,dosage,pH,and coexisting ions on phosphate adsorption were investigated to explore the adsorption mechanism and the cyclic regeneration capacity of adsorbent materials.The results showed that the phosphate adsorption process of cerium-modified drinking water treatment residual was consistent with the proposed secondary kinetics and Freundlich adsorption isotherm,and the maximum adsorption capacity was 69.43 mg·g-1.The adsorption rate was controlled by multiple factors,such as internal diffusion and the boundary layer effect.The cerium-modified drinking water treatment residual had the ability to selectively adsorb phosphate at the interference of co-existing ions such as Cl-,NO3-,CO32-,SO42-,etc.After five adsorption-desorption cycles,the removal rate of phosphate by the adsorbent material decreased by 25.4％.The adsorption mechanism is mainly electrostatic attraction and ligand exchange between phosphates and hydroxyl groups as well as cerium-containing groups.