Electrochemical Precipitation of Struvite

Pure struvite (magnesium ammonium phosphate hexahydrate) layers were deposited by an electrochemical method, from an aqueous solution containing phosphate, ammonium, and magnesium ions. According to interracial pH measurements, it was shown that the process is governed by a strong pH increase in the vicinity of the cathodic plate, due to the electrochemical reduction of oxygen and/or water molecules. The composition, the structure, and the morphology of the struvite layers were characterized by EDX analysis, X-ray diffraction, and Raman spectroscopy. Struvite electrochemical precipitation appears as an alternative method to recover P, N, and Mg from waste waters.