Tetrazole-based organoselenium bi-functionalized corrosion inhibitors during oil well acidizing: Experimental, computational studies, and SRB bioassay
By Eid, A. M.; Shaaban, S.; Shalabi, K.
Published in Journal of Molecular Liquids
2019
Abstract
Three tetrazole-based organoselenium compounds (TOS1, TOS2, and TOS3) were synthesized via Ugi and sequential Ugi/nucleophilic substitution approaches. The synthesized agents were evaluated against the corrosive effect of 10% HCl solution over J55 steel tubing samples as a simulation of the impact of a well-stimulating acid job. Chemical and electrochemical studies were conducted by means of various test methods, namely, weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy, and electrochemical frequency modulation. Furthermore, surface examinations were also performed using scanning electron microscope and X-ray photoelectron spectroscopy, which confirmed the formation of protective layer of TOS molecules on J55 steel surface. The inhibition efficiencies (%IE) of TOS1 and TOS2 were up to 92.2% and 94.6%, respectively, whereas TOS3 manifested a lower %IE (89.1%). Moreover, the assessment of TOS1, TOS2, and TOS3 inhibitors as a potential biocidal agent was accounted using NACE Standard TM0194-14 (Field Monitoring of Bacterial Growth in Oil and Gas Systems) against well annulus water samples infected with sulfate-reducing bacteria. Interestingly, all of the tetrazole-based organoselenium compounds exhibited a strong biocidal effect toward microbial-induced corrosion. Finally, quantum chemical calculations and Monte Carlo simulations were performed to provide a rationalization for the inhibitory action of the tetrazole-based organoselenium compounds.