The effect of benzotriazole (BTA) on repassivation of iron in IN H2S04 was investigated under controlled hydrodynamic conditions. The presence of BTA was found to reduce the solubility of iron sulfate and thus to enhance the ability of the system to repassivate by the dissolution-precipitation sequence. In addition, BTA was found to adsorb according to a Langmuir isotherm where the adsorption coefficient has a value, for the range of potential studied, which suggests that physical adsorption occurs. Repassivation experiments, carried out with a rotating disk system, were in agreement with theoretical predictions of flow conditions under which repassivation would, or would not, occur. It was concluded that the inhibiting action of benzotriazole in this system is caused both by adsorption, which shields a portion of the surface from experiencing the dissolution-precipitation sequence, and by lowering the solubility of the dissolution product, which speeds repassivation of the active sites.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry