The inhibitive impact of both kinds of 5-isothiocyanatomethyl-8-hydroxyquinoline derivatives on the corrosion of carbon steel in acidic electrolyte

Abstract

Two new 8-hydroxyquinoline derivatives namely 1-((8-hydroxyquinolin-5-yl)methyl)-3-methylthiourea (HQMT) and 5-isothiocyanatomethyl-8-hydroxyquinoline (TCHQ) were synthesized and identified by various spectroscopic methods (IR, NMR and Elemental analysis). The inhibitive action of 5-isothiocyantomethyl-8-hydroxyauinoline derivatives against the corrosion of carbon steel corrosion in 1 M HCl environment was examined using the conventional electrochemical, gravimetric, UV ? visible spectroscopy, SEM observations and theoretical calculation methods. The results finding indicate that the effect of preventing of HQMT is higher compared to TCHQ, and both heterocyclic compounds exhibiting excellent anticorrosive properties of carbon steel in HCl electrolyte reaches approximately 91% at10?3 M of HQMT and 89% achieved by TCHQ. Polarization curves indicate that the both compounds act as mixed type inhibitors. Moreover, the kinetic and thermodynamic parameters for the corrosion reaction were estimated and debated. - 2019 Elsevier B.V.