Inhibition Effect of Pantoprazole Drug on Under-Deposit Corrosion of Carbon Steel

Inhibition effects of pantoprazole drug on the under-deposit corrosion of carbon steel in 3.5% NaCl solution saturated with CO2 have been investigated by the techniques of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The carbon steel electrode was covered with a layer of the silica sand to prepare the sand-covered electrode. The increase of the drug concentration led to an increase in the inhibition efficiency (IE) of carbon steel against under-deposit corrosion in the brine solution. The Langmuir isotherm can describe the adsorption behavior of pantoprazole on the surface of carbon steel. Measurements of potentiodynamic polarization indicated that pantoprazole is an anodic inhibitor. The effects of temperature on the under-deposit corrosion behavior of carbon steel were studied both in the absence and presence of pantoprazole drug. The enthalpy of the drug adsorption was obtained from the temperature dependence of the corrosion inhibition process. A reasonable agreement was observed between the IE values resulted from the potentiodynamic polarization and the EIS techniques.