Experimental and Theoretical Analysis on Mild Steel Corrosion Inhibition by Two Novel Compounds (FD and ACP) in Acidic Media

• Autor(a) principal: Gopalakrishnan,Vidyadharani
• Data de Publicação: 2023
• Outros Autores: Balasubramanian,Anand, Subramanian,Loganathan, Muhammed,Rabiu Ibraheem, Garg,Rajni, Eddy,Nnabuk Okon
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042023000300223
• topic: ACP; adsorption isotherm; corrosion; EIS; FD; IE (%); MS; PDP

Abstract Two novel synthesized compounds (FD and ACP) have been applied as inhibitors for MS corrosion in HCl and H2SO4 solutions. Gravimetric, PDP, EIS, SEM and theoretical approaches were employed for the investigation of FD and ACP synthesized compounds IE%. Their corrosion IE% and calculated quantum chemical properties were comparable to each other, and indicated that ACP is a slightly less effective inhibitor than FD in HCl and H2SO4 solutions. Langmuir’s, Temkin’s, Frumkin’s and Freundlich’s adsorption isotherms were used for describing the inhibitors adsorption behavior. The adsorption was spontaneous and followed a mixed mechanism, but with initial physisorption. Polarization data revealed that the inhibitors were more cathodic, because they tended to enforce MS HER retardation. The inhibitors decreased the electrolyte impedance, while Rct increased. The adsorption mechanism was influenced by the protonation and solvation environment, and it was concentrated within the heteroatoms and the aromatic systems. Calculated quantum parameters agreed effectively with the obtained experimental results, while FF indices were useful for predicting the nucleophilic and electrophilic attacks positions.