The corrosion inhibition of mild steel in acidic media by a new triazole derivative

A new corrosion inhibitor, namely, 3,5-bis(2-thienyl)-4-amino-1,2,4-triazoles (2-TAT) has been synthesised and its inhibiting action on the corrosion of mild steel in acid baths (1 M HCl and 0.5 M H2SO4) has been investigated by various corrosion monitoring techniques, such as corrosion weight loss tests and electrochemical impedance spectroscopy. The electrochemical study reveals that this compound is an anodic inhibitor. Changes in impedance parameters (R-t and C-dl) are indicative of the adsorption of 2-TAT on the metal surface, leading to the formation of a protective film which grows with increasing exposure time. 2-TAT is able to reduce the steel corrosion more effectively in IM HCl than in 0.5 M H2SO4. The adsorption of this inhibitor is also found to obey the Langmuir adsorption isotherm in both acids. 2-TAT is considered as a non-cytotoxic substance. (C) 1999 Elsevier Science Ltd. All rights reserved.