Theoretical Approach to Evaluate the Effectiveness of Pyridinium Salts in Preventing Mild Steel Corrosion in Acidic Conditions

• Published in: Al-Nahrain Journal of Science Vol. 28; no. 2; pp. 32 - 47
• Main Authors: M. Ahmad, Shayma, Salih Shihab, Mehdi, Moayed Ahmed, Mohammed, Adnan Rashad, Alaa, Alaysuy, Omaymah
• Format: Journal Article
• Language: English
• Published: 01.06.2025
• ISSN: 2663-5453; 2663-5461
• DOI: 10.22401/ANJS.28.2.04

Pyridinium salts(namely 4-(2-(3-phenylallylidene)hydrazine-1-carbothioamido)-1-propylpyridin-1-ium bromide, A1; 3-(2-(4-(dimethylamino) benzylidene)hydrazine-1-carbothioamido)-1-ethylpyridin-1-ium bromide, A2; 3-(2-(4-(dimethylamino)benzylidene)hydrazine-1-carbothioamido)-1-propylpyridin-1-ium bromide, A3 were successfully prepared in advance, and in this study, they were examined theoretically to determine their effectiveness and efficiency as powerful mild steel corrosion inhibitors. The weight loss method was used to evaluate corrosion inhibition of these salts in 1M H2SO4media which carried out for 24 hours at room temperature. At a variety of pyridinium salt concentrations, the inhibitory efficiency results for all these salts (A1, A2, and A3) were high. The rate of corrosion is known to decrease with increasing inhibitor concentration, while at the same time, surface degree of coverage and inhibition efficiency are rising. The physisorption effects for these prepared compounds (A1, A2, and A3) were indicated by the adsorption results. For the three inhibitors under study, semi-empirical molecular orbital computations and the molecular mechanics approach were used to examine the relationship between experimental and theoretical data. To comprehend the nature of the interaction between the organic inhibitor molecules with the metal surface, theoretical simulations were performed.