Effect of Imidazole as Corrosion Inhibitor on Carbon Steel Weldment in District Heating Water

Abstract

Many research studies have been conducted on the corrosion inhibition performance of imidazole in acidic environments such as in the piping of a petrochemical plant. However, there has been no study on the effect of imidazole in alkaline conditions such as a local district water heating environment. Therefore, in this study, the effect of imidazole as a corrosion inhibitor on carbon steel weldment was investigated in alkaline district heating water. Inhibition efficiency and electrochemical properties were investigated by potentiodynamic polarization test and electrochemical impedance spectroscopy. As the concentration of imidazole increased up to 500 ppm, inhibition efficiency increased up to 91.7%. At 1000 ppm, inhibition efficiency decreased. Atomic force microscopy showed that surface coverage of imidazole at 1000 ppm is lower than that of imidazole at 500 ppm. X-ray photoelectron spectroscopy showed that with 500 ppm of imidazole, the amount of pyrrole type interaction is 4.8 times larger than pyridine type interaction. At 1000 ppm of imidazole, the amount of pyridine type interaction is 3.49 times larger than pyrrole type interaction. Depending on the concentration of imidazole, the ratio of interaction between carbon steel and imidazole affected inhibition efficiency.

Controlling Galvanic Corrosion with Oxalic Acid and Imidazole for Chemical Mechanical Planarization of Cobalt-Copper Interface

“…Besides, the slope of the anodic polarization curve increases with imidazole addition for both the metals but again to a higher extent for Co. Thus, imidazole adsorbs on these metal/metal oxide surfaces via -C=NC and -C-NH-C interactions, 84 forms a protective film and suppresses the anodic reaction rate for both the metals by blocking the active corrosive sites. However, the effect is more pronounced on Co compared to Cu as observed from polarization curves.…”

“…Effect of imidazole on SER and Co/Cu RR selectivity and in reducing Co-Cu galvanic corrosion.-Imidazole being a nitrogenous heterocyclic compound of the azole -group, is reported as an effective corrosion inhibitor for various metals such as Cu, Ru, Al. 68,81,[83][84][85][86] Thus, polishing experiments were performed to evaluate the combined effect of 1 wt% fumed silica + 0.1 wt% H 2 O 2 + 0.02 M oxalic acid solution along with 5 ppm imidazole on removal rate selectivity of Co and Cu. Prior to polishing experiments, dissolution studies were conducted to investigate the dissolution rates of the metals in the solution.…”

Técnicas experimentais e teóricas aplicadas ao estudo de inibidores orgânicos de corrosão em meio ácido

“…Em outro exemplo de utilização dessa técnica, pesquisadores publicaram recentemente resultados da avaliação experimental de inibidores de corrosão em aço carbono em meio alcalino e analisaram o seu comportamento eletroquímico e a sua eficiência de inibição em várias concentrações (Ko et al, 2021). Os autores concluíram a partir das curvas de polarização que as concentrações em 100 e 300 ppm dos derivados de imidazol analisados não são suficientes para inibir a corrosão de forma eficaz, porém nas concentrações de 500 e 1000 ppm apresentaram um comportamento passivo, o que significa que a corrosão em superfícies metálicas foi suprimida pelo imidazol adsorvido.…”