Abstract
Seven analytical and electroanalytical techniques, namely gravimetric, thermometric, gasometrical, acidimetric, atomic absorption spectroscopy (AAS), potentiodynamic polarization, and electrochemical impedance spectroscopy, EIS, were applied in the determination of ferrous (Fe
+2
) ions that result from corrosion of steel in aqueous lower pH medium, in the presence and absence of omeprazole drugs as corrosion inhibitors. The effects of pH, concentration and temperature were studied; the ferrous ion (Fe
+2
) concentration and consequently the corrosion rate decreased by increasing drug concentration, while the concentration of ferrous ions (Fe
+2
) and corrosion rate increased by lowering pH and with rising temperature. Potentodynamic polarization techniques show that the used drugs act as mixed type inhibitors for steel in all studied pH values. The maximum inhibition efficiency, obtained using 300 ppm of omeprazole drugs, is 96% within the range when it is compared with the obtained efficiency in the cited references. All the used techniques are in good agreement with each other (±2%) and show that the used drugs act as green corrosion inhibitors for the steel at lower pH values.