Electrochemical behavior of indole for AISI 430 stainless steel in changing the media from 1 mol L-1 H2SO4 to 1 mol L-1 HCl

Rem: Revista Escola de Minas

Martha Tussolini²  Aline Viomar¹  André Lazarin Gallina¹  Everson Do Prado Banczek¹  Maico Taras Da Cunha¹  Paulo Rogério Pinto Rodrigues¹ 

[1] ,State University in the MidwestGuarapuava Paraná ,Brazil

关键词: Corrosion inhibitor;    adsorption;    protonation;    Inibidor de corrosão;    adsorção;    protonação;   

DOI  :  10.1590/S0370-44672013000200012

来源: SciELO

【 摘 要 】

The adsorption of organic substances in metals and in different media has been attributed to different effects, such as the carbon chain size, type or number of heteroatom in the molecule structure, reactivity, the steric effect, among others. The objective of this work is to study the electrochemical indole behavior for AISI 430 stainless steel (SS), when changing the study media from H2SO4 1 mol L-1 to HCl 1 mol L-1. The experimental techniques used are as follows: the open-circuit potential, anodic and cathodic potentiodinamic polarization, electrochemical impedance spectroscopy, optical microscopy and scanning electron microscopy. These results suggest that the adsorption of indole in the presence of SO4-2 is lower than in the medium containing Cl-, which is justified by the indole action as a weak acid, because it has only a single pair of electrons, which is displaced and takes part in the π-electron aromatic system; thus the first step of the indole reaction in acid media is the protonation and generation of an indole cation.

【 授权许可】

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