Construction of zirconium-based active site for phosphate electro-adsorption

Excessive phosphorus in water can lead to environmental pollution problems such as eutrophication，and effective methods for removing phosphate have attracted the attention of researchers. The electrode material（ZrAC） of Zr-based metal doped activated carbon was successfully prepared by liquid-phase impregnation coupled calcination method and used for phosphorus electro-adsorption. The composite activated carbon material was characterized by XRD，XPS，SEM，EDS and TEM. The results indicated that the synthesized ZrAC material exhibited favorable crystal structure characteristics，while the incorporation of Zr provided an ample number of adsorption sites for efficient phosphate removal. The kinetics of the prepared electrode material during the phosphate removal process followed a pseudo-second-order kinetic model. At a voltage of 1.0 V，the PO43- electro-adsorption capacity could reach 29.43 mg/g，and the external voltage significantly improved the phosphate removal effect. The capture of PO43- by ZrAC was primarily attributed to the formation of Zr—O—P bond，thereby enhancing the adsorption capacity and rate of the electrode material towards PO43-. Moreover，the synthesized ZrAC electrode material exhibited excellent resistance to interference and stability during electro-adsorption.