8th. INTERNATIONAL NEW YORK CONFERENCE ON EVOLVING TRENDS IN INTERDISCIPLINARY RESEARCH & PRACTICES, New York, United States Of America, 1 - 03 May 2023, pp.220
Corrosion is one of the most important problems that
adversely affects the metal industry in economic terms. One of the most
commonly used methods in the fight against metal corrosion, which occurs more
rapidly and intensively in acidic environment, is to use corrosion
inhibitors.[1] Surfactants have been discovered to be one of the most effective
inhibitors against corrosion of iron and steel in acidic media in recent years
in order to control and reduce the corrosion rate. In accordance with the aim
of this discovery, in this study, two cationic surfactants with different
functional groups (one amide and the other ester group) attached to pyridinium
nitrogen were synthesized and their structures were confirmed by spectroscopic
methods (FT-IR and H-NMR). The inhibitory activities of these synthesized
products against corrosion of mild steel in 1.0 M HCl medium were determined
and compared among themselves. The weight loss method on metal plates was used
to determine the inhibitory activity. For this, metal plates were immersed for
24 hours in 1M HCl solutions without inhibitors and with different
concentrations of inhibitors. At room temperature of 25 oC, the corrosion inhibition
of both synthesized compounds was found to be close to each other. However, at
the lower inhibitor concentrations studied, the inhibitor containing the ester
functional group showed slightly better inhibition activity. Adsorption
isotherm studies were performed to obtain accurate information about the
corrosion inhibition mechanism. Isotherm studies based on gravimetric measurements
revealed that the adsorption of the synthesized compounds was consistent with
the Langmuir isotherm. In addition, in order to support the corrosion
inhibition efficiency results, at the end of the corrosion tests, the
morphological changes of the surface were observed by taking images of the
metal surface with an optical microscope camera.