2-Amino-1-(4-aminophenyl)-1H-pyrrolo(2,3-b)quinoxaline-3- carbonitrile as an efficient inhibitor for the corrosion of C38 steel in hydrochloric acid solution

Mounim Lebrini (1) , W. Benkayba (2) , Charafeddine Jama (3) , Fouad Bentiss (4) , Christophe Roos (1)

1 L3MA - Laboratoire des matériaux et molécules en milieu Agressif [UR4_1]
2 UM5 - Université Mohammed V de Rabat [Agdal]
3 UMET - Unité Matériaux et Transformations - UMR 8207
4 UCD - Université Chouaib Doukkali

The inhibiting properties of 2-Amino-1-(4-aminophenyl)-1H-pyrrolo(2,3-b)quinoxaline-3-carbonitrile (AHPQC) were examined of C38 steel corrosion in molar hydrochloric acid using electrochemical techniques. Impedance data displayed the AHPQC inhibits C38 steel corrosion becoming the adsorbate at metal/electrolyte interfaces. Polarization study indicated that AHPQC is an anodic-cathodic inhibitor. The inhibition efficiencies of AHPQC calculated by both methods reaches 91%. The Langmuir adsorption isotherm was observed for the AHPQC adsorption and its adsorption is realized by physical adsorption; due to the protonated forms of the AHPQC molecule in acid medium. XPS technique was used to discuss the mechanism for the adsorption process of the AHPQC molecule.

Keywords: AHPQC molecule; Molar hydrochloric acid; Inhibition; XPS; Electrochemical techniques

Domains: Other

Mounim Lebrini, W. Benkayba, Charafeddine Jama, Fouad Bentiss, Christophe Roos. 2-Amino-1-(4-aminophenyl)-1H-pyrrolo(2,3-b)quinoxaline-3- carbonitrile as an efficient inhibitor for the corrosion of C38 steel in hydrochloric acid solution. International Journal of Electrochemical Science, 2020, 15, pp.2326-2334. ⟨10.20964/2020.03.46⟩. ⟨hal-02927036⟩