Synergistic inhibition effect of rare earth cerium(IV) ion and sodium oleate on the corrosion of cold rolled steel in phosphoric acid solution

• DOI: 10.1016/j.corsci.2009.12.017
• Publication Date: 2009-12-17T13:40:44Z
• Authors: Xianghong Li; Shuduan Deng; Hui Fu; Guannan Mu
• Keywords: Phosphoric acid; Corrosion inhibitor

Abstract The synergistic inhibition effect of rare earth cerium(IV) ion (Ce 4+ ) and sodium oleate (SO) on the corrosion of cold rolled steel (CRS) in 3.0 M phosphoric acid (H 3 PO 4 ) has been investigated by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) methods. The results reveal that SO has a moderate inhibitive effect and its adsorption obeys Temkin adsorption isotherm. Ce 4+ has a poor effect. However, incorporation of Ce 4+ with SO improves the inhibition performance significantly, and exhibits synergistic inhibition effect. SO acts as a cathodic inhibitor, while SO/Ce 4+ mixture acts as a mixed-type inhibitor.