Corrosion and Corrosion Inhibition of Mild Steel in Groundwater at Different Temperatures by Newly Synthesized Benzotriazole and Phosphono Derivatives

The corrosion and corrosion inhibition of mild steel in groundwater using 1-(2-pyrrolecarbonyl)-benzotriazole (PBTA) and 1-(2-thienylcarbonyl)-benzotriazole (TBTA) with 2-phosphonoacetic acid (PAA), 4-phosphonobutyric acid (PBA), and Zn2+ at various temperatures ranging from 30 to 60 degrees C were reported. The study was performed using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) along with X-ray diffraction (XRD) and Scanning electron microscopy (SEM) investigations. PDP measurements proved that the presence of inhibitors decreases the corrosion of still by decreasing its corrosion current density. EIS data showed that the charge transfer resistance of steel increases in the groundwater containing inhibitors. XRD and SEM investigations confirmed that the inhibition of mild steel is achieved by the adsorption of the inhibitor molecules on the steel surface. All results indicated that the presence of PBTA and TBTA along with Zn2+ as well as PBA offered good inhibition efficiency against corrosion of mild steel in the groundwater media.