Effect of direct current and pulse current on CaCO3 electrodeposition

Abstract

Electrochemical deposition of CaCO3 is one of the methods to reduce scaling in industrial water system. The pulse current（PC） and direct current（DC） were used to study the electrodeposition process of CaCO3，and the influence of different ions on PC electrodeposition of CaCO3. The crystal morphology of CaCO3 were characterized by SEM and XRD. The experimental results showed that the nucleation rate of CaCO3 on 304SS electrode under PC is faster than that under DC，which promoted the ripening process of calcium carbonate. The addition of Fe3+，PO43-，SiO32- and Mg2+ accelerated the crystallization of CaCO3，but decreased the density and thickness of the deposition. The ripening process of PC electrodeposition makes the crystallization tend to form layered calcite with larger particle size，and the calcite particle size is larger than that obtained by DC electrodeposition.

Keywords

• pulse current
• electro-deposition
• calcium carbonate scale
• ripening