Abstract

KHLIFI, A. El et al. Synthesis and Corrosion Inhibition of Mild Steel in a Phosphoric Acid Solution of a Novel Benzothiazine Derivative. Port. Electrochim. Acta [online]. 2022, vol.40, n.1, pp.33-46.  Epub Feb 28, 2022. ISSN 0872-1904.  https://doi.org/10.4152/pea.2022400103.

Ethyl 3-hydroxy-2-(p-tolyl)-3,4-dihydro-2H-benzo[b][1,4]thiazine-3-carboxylate (EHBT) inhibition effect and its adsorption onto a mild steel surface in phosphoric acid (2 M H3PO4) was investigated, at temperatures varying between 298 and 328 K, by weight loss, EIS and potentiodynamic polarization techniques. The tested compound showed an inhibition efficiency that was superior to 88 % for a concentration equal to 5 × 10-3 M. Polarization measurements indicated that the examined EHBT acted as a mixed inhibitor. The protection efficiency increased with higher inhibitor concentrations and decreased with an increase in temperature. EHBT adsorption onto the mild steel surface obeyed Langmuir adsorption isotherm. EHBT inhibition action was also evaluated by surface SEM images.

Keywords : corrosion inhibition; benzothiazine; phosphoric acid; mild steel; and EIS.

        · text in English     · English ( pdf )