TITLE:
Synthesis and Evaluation of Corrosion Inhibiting Activity of New Molecular Hybrids Containing the Morpholine, 1,4-Naphthoquinone, 7-Chloroquinoline and 1,3,5-Triazine Cores
AUTHORS:
Regina Westphal, Jorge Welton de Souza Pina, Juliana Panceri Franco, Josimar Ribeiro, Maicon Delarmelina, Rodolfo Goetze Fiorot, José Walkimar de Mesquita Carneiro, Sandro José Greco
KEYWORDS:
Corrosion, Density Functional Calculations, Eletrochemical Impedance Spectroscopy, Heterocycles, Polarization
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.10 No.4,
September
22,
2020
ABSTRACT: Three molecules containing
morpholine, 1,4-naphthoquinone, 7-chloroquinoline and 1,3,5-triazine cores, scaffolds
with recognized anti-corrosive activity, were synthesized and had their
anticorrosive activity evaluated through potentiodynamic polarization and
electrochemical impedance studies. Both studies were conducted in a simulated production water medium containing 150,000 mg·L-1 Cl- and 5 mg·L-1 S2-. Corrosion
inhibition efficiency ranged from 67% - 86%, amongst which the naphthoquinone-containing derivative (compound 1)
was the most effective. These compounds act through formation of a protective
film on the surface of AISI 316 stainless steel. Investigation of the molecular
properties of the prepared inhibitors by DFT calculations revealed that the
LUMO energy and chemical hardness of the molecules can be directly correlated
with their inhibition efficiency.