Abstract
The inhibition of Stainless Steel 304L (SS (304L)) in 0.5 M H2SO4 was study by use expired levothyroxine drug as eco-friendly inhibitor. There are many techniques ((Mass loss (ML), potentiodynamic polarization (PP) tests and electrochemical impedance spectroscopy (EIS)) utilized in this study to explain the protection process. The corrosion inhibition (%IE) rise with improving doses of the expired levothyroxine drug and reduction by temperature raising. The activation and adsorption parameters were calculated and discussed. %IE of SS (304L) occurs by the adsorption process, and this SS (304L) is subject to the adsorption of Langmuir. From the EIS examination, we notice the reduction of the double layer by raising the concentration of expired levothyroxine drug, on the other hand, the charge transfer resistance is increased. The surface morphology of SS (304L) metal was examined by employing various techniques such as AFM, FTIR, SEM and EDX. Results were of all techniques used are in excellent coherence.