Adsorption and Corrosion Inhibition Behavior of Carbon Steel by Cefoperazone as Eco-Friendly Inhibitor in HCl

The inhibition effect of cefoperazone (CP) on the corrosion behavior of carbon steel in 0.5 M HCl solution was studied using potentiodynamic polarization, electrochemical impedance spectroscopy, and electrochemical frequency modulation techniques along with scanning electron microscopy (SEM). Results showed that the inhibition efficiency increases with increasing inhibitor concentration and decreases with increasing the temperature. The results indicated that the inhibitive action of CP can be attributed to its adsorption. The results show that CP possesses excellent inhibiting effect for the corrosion of carbon steel and the inhibitor acts as mixed-type inhibitor. The adsorption process is spontaneous and follows Langmuir adsorption isotherm model. The surface adsorption of the inhibitor molecules decreases the double-layer capacitance and increases the polarization resistance. SEM results indicate the formation of an adsorbed protective film on the metal surface. The results obtained from the different techniques were in good agreement which prove the validity of these tools in the measurements of the tested inhibitor.