Corrosion inhibition of thiadiazole derivative for mild steel in hydrochloric acid solution

Abstract

In the various industries such as pickling, gas and oil industries in which an acid medium, especially hydrochloric acid, is used, the corrosion of mild steel significantly increases destruction with a huge financial loss. The best method for preventing corrosion of mild steel alloy is to use an impermeable layer over the target alloy. The coatings are not constantly impervious, and all coating techniques finally fail for various reasons and therefore, anti-corrosion agents are added. The inhibition impact of new corrosion inhibitor entitled “5,5´-(1,4-phenylene)bis(N-benzylidene-1,3,4-thiadiazol-2-amine)” (PBTA) on the surface of mild steel corrosion in 1 M HCl media was studied using weight loss techniques. The surface of mild steel was exposed to investigated solution and evaluated using scanning electron microscopy (SEM). Effects of the concentration of PBTA, acidic content, temperature variation and immersion time were investigated. PBTA has excellent inhibitive performance on the corrosion of mild steel in 1 M HCl solution and enhanced with an increase in PBTA inhibitor concentration, while decreasing with a decrease in immersion time and corrosion temperature. The adsorption of the synthesized corrosion inhibitor on the surface of mild steel obeys the Langmuir adsorption isotherm. Various spectroscopic techniques such as1H NMR (Proton nuclear magnetic resonance),13C NMR (Carbon-13 nuclear magnetic resonance) and FTIR (Fourier-transform infrared) were used for confirmation of the structure of the corrosion inhibitor molecule.