ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Electrochemical, morphological and theoretical studies of an oxadiazole derivative as an anti-corrosive agent for kerosene reservoirs in Iraqi refineries

Eva Adel Yaqo, Rana Afif Anaee, Majid Hameed Abdulmajeed, Ivan Hameed R. Tomi, and Mustafa Mohammed Kadhim

Department of Materials Engineering, University of Technology, Baghdad, Iraq

E-mail: ivanhrtomy@uomustansiriyah.edu.iq

Received: 7 September 2019  Accepted: 3 December 2019

Abstract:

An oxadiazole derivative 4-[3-(4-methylphenyl)-1,2,4-oxadiazol-5-yl]-phenol (MOP) has been investigated as a protector against corrosion of mild steel tanks in Iraqi kerosene reservoirs using the Tafel approach. The extrapolation study was carried out in four temperatures (303, 313, 323 and 333 K) and five concentrations (100, 200, 300, 400 and 500 ppm) of MOP derivative. The results of the polarization study showed that the MOP inhibitor is classified as a mixed type and the activity of corrosion inhibition was estimated depending on Tafel curve. The highest performance of the inhibition efficiency (IE% = 88.95) was observed in 500 ppm of the MOP inhibitor at 303 K, and the results showed that the increase of IE% was related to increase in the temperature and concentration of the inhibitor. The calculated thermodynamic parameters confirmed that the nature of adsorption is physisorption and the inhibitor obeys Langmuir isotherm. Different morphological methodologies have been used to confirm the protected layer formation on the steel surface. Also, Fourier transform infrared (FT-IR) spectrophotometer was used to detect the interference method between the inhibitor and surface. The computational study was applied to show the active locations of inhibitor and study their relationship with the surface by density functional theory (DFT). Also, the biological efficacy of this inhibitor has been shown to have a good inhibition zone against some types of corrosive bacteria.

Keywords: Low carbon steel; 1,2,4-Oxadiazole; Tafel curve; Theoretical calculation

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-01022-2

Chemical Papers 74 (6) 1739–1757 (2020)