Experimental investigation for corrosion inhibition of mild steel in hydrochloric acid bath by 3-[(5-phenyl-1,3,-thiadiazol-2-yl)imino]-2-oxoindoline

Abstract

We examined the anti-corrosion activity of mild steel corrosion in hydrochloric acid (1 M) media caused by the Schiff base 3-[(5-phenyl-1,3,4-thiadiazol-2-yl)imino]-2-oxoindoline. Weight-loss measurements and scanning electron microscopy were performed during the investigation. The measurements showed that the inhibition efficiency of chemical compound increased with its increasing concentration. This inhibitor functioned through adsorption following the Langmuir isotherm and the electronic properties obtained through the Austin Model 1. Semi empirical method was found to be correlated with the inhibitor’s experimental efficiency by the nonlinear regression method. The organic compound was synthesized effectively through a reaction between indoline-2,3-dione and 5-amino-2-phenyl-1,3,4-thiadiazol. Various spectroscopic techniques were used to characterize the synthesized inhibitor.