ABSTRACT
Corrosion inhibition of mild steel (MS) in 1M hydrochloric acid (HCl) medium and 1M sulfuric acid (H2SO4) medium by sulfadimidine (SDE) have been studied by weight loss method, electrochemical measurements, SEM and quantum chemical studies. The weight loss studies were conducted at different temperatures (30°C, 40°C, 50°C & 60°C) using various concentrations of SDE (0,25,50, 100, 150,200,250,300,400 & 500ppm) and at two time intervals (1h and2h). Inhibition efficiency was found to increase with increasing SDE concentration. It is found that SDE produces corrosion inhibition through adsorption obeying Temkin's adsorption isotherm. The ΔGads values reveal the type of adsorption to be physisorption. The Ea values for corrosion process determined using Arrhenius equation also support this. The recorded polarization data showed that the corrosion resistance was greatly enhanced in the presence of increasing SDE concentrations which was complimented by impedance measurements. SDE acts as anodic type of inhibitor. Surface examination using SEM revealed the protection efficiency of SDE which was complimented by quantum studies.
