3,5‐Bis(2‐thienyl)‐4‐amino‐1,2,4‐triazole as a corrosion inhibitor for copper in acidic media

Abstract

PurposeThe aim of this paper is to investigate inhibition of copper corrosion by 3,5‐bis(2‐thienyl)‐4‐amino‐1,2,4‐triazole (2‐TAT) in 1 M HCl and 0.5 M H2SO4.Design/methodology/approachPotentiodynamic polarization curves and electrochemical impedance measurements were carried out on copper in 1 M HCl and 0.5 M H2SO4 containing various concentrations of 2‐TAT, and the effects of temperature were also investigated.FindingsAs an efficient inhibitor, 2‐TAT behaves better in 1 M HCl than in 0.5 M H2SO4. 2‐TAT can be classified as cathodic‐type corrosion inhibitor in 1 M HCl and acts as relatively mixed type in 0.5 M H2SO4. Activation energies in the presence and absence of 2‐TAT were obtained by measuring the temperature independence of corrosion current. Adsorption of the inhibitor on the copper surface was found to obey the Langmuir adsorption isotherm.Practical implicationsThis inhibitor could have application in industries where hydrochloric acid solutions are used to remove scale and salts from copper surfaces and may render dismantling unnecessary.Originality/valueThe results from this paper showed that 2‐TAT could be considered as a suitable inhibitor for copper in acidic media.