Corrosion Inhibition of Expired Dogmatil Drug on Carbon Steel in HCl Solution: Experimental and Theoretical Approaches

This study demonstrates the use of several methods to suppress corrosion as well as the use of an expired medication termed expired Dogmatil drug (EDD), which functions as a corrosion inhibitor for CS in 1M HCl. In this case, an analysis using weight loss (WL) and electrochemical measurements was conducted. At 150 ppm and 318 K, EDD produced an inhibitory efficiency (IE) of 98.3%. The %IE rises with increasing drug dose and solution temperature. The EDD adsorption on the CS surface followed the Langmuir adsorption isotherm. Furthermore, because EDD operates on both anodic and cathodic processes, it unifies its many protective qualities, making it a mixed-type inhibitor. The computed thermodynamic and activation parameters were examined in order to gain a deeper understanding of the inhibitive process. The computational results showed that the drug prevented CS from corroding by forming a barrier that protected it from acid attack. The experimental findings were supported by these validated outcomes. Fourier-transform infrared spectroscopy (FTIR) analysis, atomic force microscopy (AFM), energy-dispersive X-ray (EDX), and scanning electron microscopy (SEM) all support this adsorption. Both the chemical and electrochemical measurement results show good agreement with one another.