The effect of oxalic acid on the corrosion of carbon steel

Abstract

The effect of oxalic acid (OA) on corrosion resistance of carbon steel in sulphuric acid pH=2.5‐6.0 solutions containing 10⁻⁷‐10⁻³M OA was investigated by means of potentiodynamic polarisation measurements and immersion tests. The results suggest that OA is a good corrosion inhibitor for carbon steel, exhibiting inhibition efficiencies (IE) ranging from 50 to 85 per cent in dilute 10⁻⁷‐10⁻⁵M OA solutions of pH>3.0, whereas for pH≤3.0 solutions, an increase in corrosion rate was found. Non‐accelerated experiments (weight loss tests) carried out by immersing carbon steel specimens into OA‐containing solutions during at least 6 h revealed only positive IE values, regardless of both solution pH and OA content. The results were explained considering the solution composition as function of pH.

Citation

Giacomelli, C., Giacomelli, F.C., Baptista, J.A.A. and Spinelli, A. (2004), "The effect of oxalic acid on the corrosion of carbon steel", Anti-Corrosion Methods and Materials, Vol. 51 No. 2, pp. 105-111. https://doi.org/10.1108/00035590410523193