Investigation on the synthesis of a triazine derivative and its corrosion inhibition performance in CO 2 -saturated brine

Abstract

The objective of developing effective triazine-based corrosion inhibitors aims to mitigate the significant issue of corrosion in carbon steel pipelines within oil and gas field environments. In the present study, we synthesised a corrosion inhibitor designated as ST-2 through a two-step process utilising melamine, octylamine, diethylenetriamine and ethanedioic acid as precursor materials. The structural characterisation of ST-2 was conducted using Fourier transform infra-red spectroscopy and proton nuclear magnetic resonance spectroscopy. The performance of ST-2 in inhibiting corrosion at a temperature of 90°C was evaluated through static weight loss and electrochemical techniques, which demonstrated a corrosion inhibition efficiency of 92.14% at a concentration of 200 mg/L. The structure–activity relationship and film-forming mechanism of ST-2 were investigated through the application of functional theory and molecular dynamics simulations. The results revealed that the heteroatoms present in the molecule exhibited significant interactions with the metal substrate. At a corrosion inhibitor concentration of 200 mg/L, the absolute value of the adsorption energy was determined to be 1084.74 kcal/mol. Under these experimental conditions, the resulting corrosion inhibitor film exhibited maximum thickness, optimal densification and enhanced corrosion inhibition performance.