ELECTROCHEMICAL INVESTIGATION AND MODELING OF CARBON DIOXIDE CORROSION OF CARBON STEEL IN THE PRESENCE OF ACETIC ACID

Weight loss (WL) and linear polarization resistance (LPR) measurements have been used to verify the effect of acetic acid (HAc) on the anodic and cathodic reactions in CO2 corrosion of carbon steel. The experiments were performed using a standard rotating cylinder three-electrode system, in a 3% NaCl solution, in a temperature range of 22-60°C and at pH 4. The HAc concentration range used in the study was 0-1000 ppm. An electrochemical model has also been developed to predict the experimental potentiodynamic sweeps and corrosion rates which were compared with the weight loss and LPR measurements. In another modeling development, an additional term has been added to the latest de Waard corrosion model to account for HAc. The modified de Waard model was also compared to the experimental measurements.