Hydrogenated Dimer Acid as a Corrosion Inhibitor for Lead Metal Substrates in Acetic Acid

Abstract

© 2015 The Electrochemical Society. The surface characteristics of a lead carboxylate coating induced on a lead substrate using a dimer acid are discussed together with its effectiveness against acetic acid corrosion. Thermogravimetric analysis and differential scanning calorimetry were used to examine the thermal properties of the hydrogenated dimer acid and its corresponding sodium salt. Scanning electron microscopy with energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and infrared spectroscopy were used to visualize and characterize the deposited coatings on the lead substrate. Both the free dimer acid and the corresponding sodium salt formed a protective layer of lead carboxylate complexes through a reaction with the lead substrate. Single-sine electrochemical impedance spectroscopy and potentiodynamic polarization measurements of the bare and coated samples assessed the corrosion resistance of the coatings. Under the corrosive acetic acid test conditions, the lead-dimer-coated samples corroded more slowly than the bare lead.