Synergistic Inhibition Effect of 3-Carboxypyridine and Potassium Iodide on Mild Steel Corrosion in H2SO4: Electrochemical and Surface Analyses

• Main Author: Dheer,Neelu
• Publication Date: 2024
• Other Authors: Kalra,Amarpreet K., Singh,Darshan, Ujjain,Sanjeev Kumar, Ahuja,Preety, Singh,Gurmeet, Singh,M. Ramananda, Kanojia,Rajni
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042024000100059
• topic: AFM; corrosion; CP; EIS; IE (%); KI; MS; SM; SEM

Abstract The effective inhibition of MS corrosion in H2SO4 by CP and CP + KI was assessed by EIS. SM of MS was studied using SEM and AFM. The rise in Rct and decrease in Cdl, with higher C of CP only and CP + KI, confirmed MS CI. IE (%) increased with higher C of CP only and CP + KI (from 10-3 to 10-1 M). CP’s maximum IE (%) was 93.9%, at 10-1 M. CP + KI, due to I- ions synergistic effect, showed an IE (%) of about 98.8% at 10-1 M. CP only and CP + KI adsorption mechanism followed Langmuir’s isotherm. SM studies suggested that a barrier film of CP only and CP + KI, mitigated MS surface corrosion. CP + KI is an efficient inhibitor in H2SO4.