Influence of 5-Chlorobenzotriazole on Inhibition of Copper Corrosion in Acid Rain Solution

ACS Omega. 2020 May 29;5(22):12832-12841. doi: 10.1021/acsomega.0c00553. eCollection 2020 Jun 9.

Abstract

This paper aims to examine the efficiency of 5-chlorobenzotriazole (5Cl-BTA) as a copper corrosion inhibitor in acidic rain solutions with a pH value of 2.42 by the electrochemical polarization method. 5-Chlorobenzotriazole acts similar to a mixed type inhibitor, according to the potentiodynamic polarization measurements. Results obtained in this research suggest that 5Cl-BTA is a good inhibitor; it decreases anodic and cathodic reaction rates, and the highest inhibition efficiency was 91.2%. The inhibitory effect of 5-chlorobenzotriazole is explained by the formation of the layer on the copper surface. Stability of the protective layer increased with inhibitor concentration. Scanning electron microscopy and energy-dispersive analysis of X-rays analysis confirmed that on the electrode surface, a protective layer was formed. Adsorption of 5Cl-BTA obeys the Langmuir adsorption isotherm. 5Cl-BTA showed good inhibitory characteristics even when the Cl- ions were present in examined solutions.