Novel ecofriendly corrosion inhibition of mild steel in strong acid environment: Adsorption studies and thermal effects

Abstract

A new ecofriendly coumarin derivative, namely 4-((4-amino-1H-1,2,4-triazole-5(4H)-thione-3-yl)methyl)coumarin (ATMC), was synthesized and the chemical structure was elucidated using Fourier Transform Infrared Spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR) and elemental analysis (CHN). ATMC was evaluated as a corrosion inhibitor and the concentrations were 0.1 mM to 0.5 mM for mild steel in 1 M hydrochloric acid in the temperature range of 303–333 K using gravimetric and surface analysis by means of scanning electron microscopy (SEM) techniques. The gravimetrical results show that ATMC inhibited the corrosion of mild steel in a strong acid solution with superior performance. It was found that the corrosion inhibition performance depends on the concentration of the studied inhibitor and the solution temperature. The inhibition efficiency increased with an increase in the concentration of the inhibitor and reached 96.5% at a concentration of 0.5 M and 303 K. Experimental and adsorption results are in good agreement.