Phosphate removal from aqueous solution by electrochemical coupling siderite packed column

Abstract

The use of iron species to remove PO43− is widely used, and the fresh Fe3+ produced in situ demonstrate better effect on the removal of PO43− in many researches. Therefore, in order to develop a simpler and more efficient method for PO43− removal, we designed an easy operation by electrochemically dissolving siderite to produce fresh Fe3+ in situ for PO43− removal from wastewater. Results showed that current intensity at 20 mA, initial pH at 6, initial PO43− concentration at 1 mM and influent flow rate at 2.5 mL min−1 were the best parameters for removing PO43−, ensuring that the PO43− concentration of effluent can be kept below 1 mg L−1 through the electrochemical system. Different from other studies, a large amount of Fe2+ can be dissolved from natural minerals without adding H+ to the system and Fe3+ species are generated in situ from the oxidation of the Fe2+ without using a specific oxidizer. This electrochemical treatment method with siderite as a packed column can be used as a new method of high efficiency, simple operation and low-cost for treating eutrophic water bodies.