Experimental and theoretical examinations of two quinolin-8-ol-piperazine derivatives as organic corrosion inhibitors for C35E steel in hydrochloric acid

The mitigation impacts of two quinolin-8-ol-piperazine analogs 7-((4-(benzo[d][1,3]dioxol-5-ylmethyl) piperazin-1-yl)methyl)quinolin-8-ol (OPMQ) and 7-((4-benzylpiperazin-1-yl)methyl)quinolin-8-ol (BPMQ) on the C35E steel corrosion in 1 M HCl environment were examined by gravimetric, electrochemical, surface analysis, electrolyte analysis, as well as molecular modeling techniques. The examined OPMQ and BPMQ exhibited obvious anticorrosion performances within the scope of concentrations and temperature considered, maximum reached of 95.1% and 88.7% at 10(-3) M, respectively. Polarization examinations demonstrated that the OPMQ and BPMQ being as mixed-type inhibitors. Moreover, the quinolin8-ol-piperazine analogs adsorption obeyed the Langmuir adsorption isotherm, presenting chemical interactions. Thermodynamic and kinetic quantities were estimated and discussed. Uv/Visible spectra proved the occurrence of chemical interaction among the C35E steel and quinolin-8-ol-piperazine analogs molecules, while no damages have been observed in the SEM images after the addition of quinolin-8-olpiperazine analogs adsorption to the corrosive electrolyte. The computational correlations (DFT and Molecular Dynamic simulations) justify the experimental observations. (c) 2022 Elsevier B.V. All rights reserved.

Automated summary

The mitigation impacts of two quinolin-8-ol-piperazine analogs, OPMQ and BPMQ, on the corrosion of C35E steel in 1M HCl environment were examined. The results showed that both OPMQ and BPMQ exhibited significant anticorrosion performances. Polarization examinations revealed that they acted as mixed-type inhibitors, and the adsorption of the analogs followed the Langmuir adsorption isotherm, indicating chemical interactions. Computational correlations supported the experimental findings.