Author(s)

Regina Westphal¹, Jorge Welton de Souza Pina¹, Juliana Panceri Franco², Josimar Ribeiro², Maicon Delarmelina^3,4, Rodolfo Goetze Fiorot³, José Walkimar de Mesquita Carneiro³, Sandro José Greco^1*

¹Laboratório de Síntese Organica Aplicada, Departamento de Química, Universidade Federal do Espírito Santo, Vitória, Brasil.
²Laboratório de Pesquisa e Desenvolvimento em Eletroquímica, Departamento de Química, Universidade Federal do Espírito Santo, Vitória, Brasil.
³Laboratório de Química Computacional, Instituto de Química, Universidade Federal Fluminense, Niterói, Brasil.
⁴Today at School of Chemistry, Cardiff University, Cardiff, United Kingdom.

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 S^2-. 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.

Corrosion, Density Functional Calculations, Eletrochemical Impedance Spectroscopy, Heterocycles, Polarization

Westphal, R. , de Souza Pina, J. , Franco, J. , Ribeiro, J. , Delarmelina, M. , Fiorot, R. , de Mesquita Carneiro, J. and Greco, S. (2020) 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. Advances in Chemical Engineering and Science, 10, 378-398. doi: 10.4236/aces.2020.104024.