Experimental and Theoretical Studies on Acid Corrosion Inhibition of API 5L X70 Steel with Novel 1-N-α-d-Glucopyranosyl-1H-1,2,3-Triazole Xanthines

Abstract

A series of novel 1-N-α-d-glucopyranosyl-1H-1,2,3-triazole xanthines was synthesized from azido sugars (glucose, galactose, and lactose) and propargyl xanthines (theophylline and theobromine) using a typical copper (I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition. The corrosion inhibition activities of these new carbohydrate-xanthine compounds were evaluated by studying the corrosion of API 5 L X70 steel in a 1 M HCl medium. The results showed that, at 10 ppm, a 90% inhibition efficiency was reached by electrochemical impedance spectroscopy. The inhibitory efficiency of these molecules is explained by means of quantum chemical calculations of the protonated species with the solvent effect, which seems to better represent the actual situation of the experimental conditions. Some quantum chemical parameters were analyzed to characterize the inhibition performance of the tested molecules.

Guar Gum as an Eco-Friendly Corrosion Inhibitor for N80 Carbon Steel under Sweet Environment in Saline Solution: Electrochemical, Surface, and Spectroscopic Studies

“…The EDS analysis (Figure 9d) shows that, in the presence of GG, the concentration of carbon and oxygen elements is much higher compared to the uninhibited one. Notably, carbon and oxygen are part of the chemical composition of GG, hence it can be inferred that GG, after its adsorption, can form a protective layer that is capable of mitigating sweet corrosion, in agreement with the findings reported in the literature [4,15,40]. As the temperature increases, the corrosion rate also increases, and both surfaces appear damaged (Figure 10a,c) even though, in the presence of GG, the surface of the metal appears less damaged, with the presence of scratches resulting from the polishing process still visible.…”

Novel porphyrin derivatives as corrosion inhibitors for stainless steel 304 in acidic environment: synthesis, electrochemical and quantum calculation studies

“…11 ), inhibitor adsorption, and deviations in the properties or compositions of layers surface 59 , 60 , “which can be connected to the frequency dispersion effect. The curves described by a single capacitive semicircle, indicates that the corrosion process was mainly charged-transfer controlled” 61 . Equation ( 12 ) describes the impedance of a constant phase element (CPE):

Figure 11 Nyquist plots for SS304 corrosion in the 2 M HCl solutions in the existence and nonexistence of various doses of porphyrin derivatives at 25 °C.

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Current Overview of Corrosion Inhibition of API Steel in Different Environments

“…In the past decade, natural-origin CIs for API steel intended to be exposed to HCl have been developed such as plant extracts, , carbohydrates, , and biopolymers, ,, including organic/inorganic nanocomposites . Particularly, the proposals based on plant extracts have become popular due to the wide variety of organic active compounds that have outstanding features such as biodegradability, bioavailability, sustainability, and nontoxicity; the high availability of this raw matter implies an additional benefit that is reflected in the diminution of synthesis costs. ,, …”

“…Afterward, the research work was extended through the synthesis of new compounds derived from glucopyranose, mannopyranose, and hexahydropyran, and it was concluded that the carbohydrate modification did not exert any significant effect on the IE of the compounds, which was equal to 76.4 and 87.5% and attributed to the presence of −OH in molecule rings; these results suggested that the addition of functional groups during the synthesis process led to IE diminution. Meanwhile, Sánchez-Eleuterio et al 32 evaluated six new carbohydrate–xanthine conjugates linked through a 1,2,3-triazole ring for API 5L X70 steel in 1 M HCl. During the EIS tests, it was observed that the compounds featuring theobromine or theophylline + glucose or galactose ( 3b – d , Table 2 ) presented IE > 90% from C INH at 20 ppm.…”