Novel glycoluril pharmaceutically active compound as a green corrosion inhibitor for the oil and gas industry

Exploring the synthesis, characterization, and corrosion inhibition of new tris-thiosemicarbazone derivatives for acidic steel settings using computational and experimental studies

A novel two tri-thiosemicarbazones derivatives, namely 2,2',2''-((2-Hydroxybenzene-1,3,5-triyl)tris(methanylylidene))tris(N-benzylhydrazine-1-carbothioamide) (HBC) and 2,2',2''-((2-hydroxybenzene-1,3,5-triyl) tris (methanylylidene)) tris (N-allylhydrazine-1-carbothioamide) (HAC), have been synthesized and their chemical structures were determined using different spectroscopic and analytical approaches. Then, utilizing methods including open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy, the inhibitory effect of the synthesized thiosemicarbazones on mild steel (MS) in an acidic environment (0.5 M H2SO4) was thoroughly investigated. Remarkably, raising the concentration of our recently synthesized tri-thiosemicarbazones HBC and HAC increased the inhibitory efficiency values. The η values of the two investigated tri-thiosemicarbazones derivatives (HAC and HBC), at each concentration are extremely high, and the maximum values of the efficiencies are 98.5% with HAC and 98.8% with HBC at the 800 ppm. The inhibitors adsorbed on the mild steel surface and generated a charge and mass movement barrier that protected the metal from hostile ions. According to polarization curves, HBC and HAC act as mixed-type inhibitors. Electrochemical impedance testing revealed a notable rise in charge transfer resistance (Rct) readings to 4930-Ω cm2, alongside a reduction in the Constant Phase Element (CPE) value to 5.81 μF, suggesting increased effectiveness in preventing corrosion. Also, density functional theory (DFT) was applied to investigate the assembled tri-thiosemicarbazones HBC and HAC. Moreover, the adsorption mechanism of HBC and HAC on the mild steel surface was explored using Monte Carlo simulation. Finally, the theoretical outputs were discovered to support the practical outcomes.

Electrochemical and DFT Studies of the Pistacia Integerrima Gall Extract: An Eco-friendly Approach towards the Corrosion of Steel in Acidic Medium

A novel application of the Pistacia integerrima gall extract as an environmentally friendly corrosion inhibitor is reported in this study. The major phytochemicals present in the gall extract, namely pistagremic acid, β-sitosterol, pistiphloroglucinyl ether, pistaciaphenyl ester, naringenin, and 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one, play key roles in its anticorrosive behavior on steel in aggressive media. Several approaches were used to study the corrosion prevention activity of steel in 1 M H2SO4, including weight loss analysis, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and density functional theory (DFT). At 2000 mg L-1, the highest efficiency of 92.19% was observed in 1 M H2SO4. An SEM study was conducted to validate the surface coverage of the metal surface. DFT studies revealed several nucleophilic regions present in the phytochemicals of the inhibitor, which supported the favorable nucleophilicity. Corrosion studies have not been performed on this sample. Phytochemicals make it an effective corrosion inhibitor, and its extraction process utilizes distilled water, making it better than other inhibitors. It has been proven that the obtained values of ΔEInhDFT for pistiphloroglucinyl, pistaciaphenyl ether, and naringenin organic compounds were very low, confirming the high reactivity of these corrosion inhibitors. The order of the values of ΔEInhDFT is as follows: pistaciaphenyl ether > pistiphloroglucinyl ether > naringenin organic compound; this suggests that pistaciaphenyl ether is more reactive than the other compounds. In this study, P. integerrima gall extract emerges as a novel and highly effective corrosion resistance agent in 1 M H2SO4, chosen for its relevance to acid pickling and cleaning processes.

Synthesis of Novel Phosphorus-Containing Derivatives of 1,3,4-Trimethylglycoluril via the Birum-Oleksyszyn Reaction

This work presents the synthesis of a new compound, 1-[aryl-(diphenylphosphono)methyl]-3,4,6-trimethylglycolurils, via the interaction of benzaldehyde and its mononitro- and monohydroxyderivatives with 1,3,4-trimethylglycoluril and triphenylphosphite. By varying the reaction conditions and the catalysts, the obtained product yields ranged from satisfactory to good. The diastereomers formed during the reaction were separated by semipreparative HPLC on the C18 stationary phase. The isolated diastereomers were characterized by 1H, 13C, and 31P NMR, and the structures of the diastereomers were confirmed using a single-crystal X-ray crystal structure analysis and quantum chemical calculations.

Novel biphenylidene-thiopyrimidine derivatives as corrosion inhibitors for carbon-steel in oilfield produced water

The inhibiting efficiency of three newly synthesized organic compounds:5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-1,3-diethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1228), 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1227) and 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)pyrimidine-2,4,6(1H,3H,5H)-trione (HM-1226) in oilfield produced water on the corrosion of carbon steel has been examined via electrochemical measurements; potentiodynamic polarization (PDP) and electrochemical impedance (EIS) techniques. The adsorption of these compounds on the surface of carbon steel followed Langmuir isotherm. In addition, the surface morphology of uninhibited and inhibited carbon steel was examined by Atomic Force Microscopy (AFM), observing surface improvement when carbon steel samples exposed to the inhibited corrosive solutions. The average surface roughness (Ra) in oilfield produced water solution in the presence of 0.5 mM of HM-1228 inhibitor was 138.28 nm compared to the uninhibited surface 571.62 nm. To explore the corrosion inhibition mechanism, quantum chemical calculations and Monte Carlo simulations were utilized. The HM-1228 inhibitor demonstrated the highest corrosion inhibition efficiency at 94.8% by PDP measurements. The higher corrosion inhibition of compound HM-1228 can be attributed to the presence of di-N-ethyl groups that enhance both electron donating ability and lipophilic properties.

Electrochemical, surface morphological and computational evaluation on carbohydrazide Schiff bases as corrosion inhibitor for mild steel in acidic medium

Anticorrosion and adsorption behaviour of synthesized carbohydrazide Schiff bases, namely (Z)-N'-(4-hydroxy-3-methoxybenzylidene)-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbohydrazide(MBTC) and (Z)-N'-(3,4-dichlorobenzylidene)-6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbohydrazide (CBTC) was examined for mild steel (MS) in 15% HCl medium. The corrosion inhibition study was performed by using gravimetric, thermodynamic, electrochemical and theoretical studies including density functional theory (DFT), molecular dynamic simulation (MDS) and Monte Carlo simulations (MCS). The outcomes in terms of corrosion inhibition efficiency using electrochemical impedance spectroscopy (EIS) method at 303 K and 150 ppm concentration were 96.75% for MBTC and 95.14% for CBTC. Both inhibitors adsorbed on the MS surface through physical as well as chemical adsorption and followed the Langmuir isotherm. The mixed-type nature of both inhibitors was identified by polarization results. Surface analysis was done using FESEM, EDX, AFM and XPS studies and results showed that a protective layer of inhibitor molecules was developed over the surface of MS. The results of DFT, MCS and MDS are in accordance with experimental results obtained by weight loss and electrochemical methods.

Comprehensive evaluation of corrosion inhibition performance and ecotoxicological effect of cinchona IIa as a green corrosion inhibitor for pickling of Q235 steel

Here, to prevent the corrosion of Q235 steel in the pickling and discover novel green corrosion inhibitors, the corrosion inhibition performance and eco-toxicity of cinchonain IIa were evaluated. Electrochemical experiments confirms that 200 mg/L cinchonain IIa reveals good corrosion inhibition performance with 94.08% on Q235 steel in HCl for 48 h. Scanning electron microscope (SEM) and atomic force microscope (AFM) observations suggest that cinchonain IIa can be firmly attached to the metal surface by forming a barrier film. The X-ray photoelectron spectroscopy (XPS) results further verify the bonding interaction between the functional groups and the steel matrix, and indicate the existence of protective film on the steel. Meanwhile, the inhibition mechanism at the molecular/atomic level is revealed through molecular dynamics simulation. Additionally, acute toxicity test shows that cinchonain IIa is a low toxic corrosion inhibitor. Moreover, the antioxidant enzyme activity experiments confirm that cinchonain IIa discloses no obvious damage to the antioxidant system of zebrafish. Overall, cinchonain IIa exhibits low potential risks to the healthy development of aquatic organisms and ecosystems. As a proven green and low toxic corrosion inhibitor, cinchonain IIa has a sustainable application in the anti-corrosion industry.

Insight into the corrosion mitigation performance of three novel benzimidazole derivatives of amino acids for carbon steel (X56) in 1 M HCl solution

Three new organic molecules having a benzimidazole base were synthesized and used for the protection of carbon steel (X56) against corrosion in 1.00 M HCl solution. The protection against corrosion was assessed by electrochemical frequency modulation (EFM), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). In addition, the electronic and molecular structure of the synthesized molecules were computationally investigated and correlated to corrosion inhibition. Global reactivity descriptors, molecular orbitals (FMO and NBO) and local reactivity descriptors (molecular electrostatic potential map and Fukui functions) were discussed. The results showed a maximum protective efficiency range between 95% and 98% indicating high corrosion inhibition. Moreover, all molecules were able to combat the cathodic as well as anodic reaction simultaneously, revealing a mixed-type resistance. SEM and EDX verified effective adhering film formation to the metal surface. In accordance, the theoretical calculations showed effective electron reallocation from the organic film to the X56 c-steel surface. Furthermore, the adsorption annealing calculations revealed that structural layers of these molecules hold parallel and close to the metal surface with adsorption energy from 249.383 to 380.794 kcal mol^-1, showing strong inhibitor-metal contact.

Essential Oil of Origanum vulgare as a Green Corrosion Inhibitor for Carbon Steel in Acidic Medium

In this study, Oregano (Origanum vulgare) leaf essential oil was studied as an environmental-friendly anticorrosion agent for carbon steel in aggressive hydrochloric acid. The corrosion inhibition of O. vulgare was characterized by surface morphology, electrochemical, weight loss, theoretical and computational methods. It was found that the highest inhibition performance of O. vulgare was 85.64% at 2 g/l in 1 M HCl. The results of Langmuir isotherm and adsorption thermodynamics investigation demonstrated that the O. vulgare inhibitor adsorbed on the metal surface by the formation of rigid covalent bonds. The adsorption and inhibition centers of the selected inhibitor were studied by the computational methods, resulting in that the hydroxyl functional groups and benzoyl rings are mainly responsible for the high inhibition efficiency.

Coco Monoethanolamide Surfactant as a Sustainable Corrosion Inhibitor for Mild Steel: Theoretical and Experimental Investigations

Recent studies indicate that surfactants are a relatively new and effective class of corrosion inhibitors that almost entirely meet the criteria for a chemical to be used as an aqueous phase corrosion inhibitor. They possess the ideal hydrophilicity to hydrophobicity ratio, which is crucial for effective interfacial interactions. In this study, a coconut-based non-ionic surfactant, namely, coco monoethanolamide (CMEA), was investigated for corrosion inhibition behaviour against mild steel (MS) in 1 M HCl employing the experimental and computational techniques. The surface morphology was studied employing the scanning electron microscope (SEM), atomic force microscope (AFM), and contact measurements. The critical micelle concentration (CMC) was evaluated to be 0.556 mM and the surface tension corresponding to the CMC was 65.28 mN/m. CMEA manifests the best inhibition efficiency (η%) of 99.01% at 0.6163 mM (at 60 °C). CMEA performs as a mixed-type inhibitor and its adsorption at the MS/1 M HCl interface followed the Langmuir isotherm. The theoretical findings from density functional theory (DFT), Monte Carlo (MC), and molecular dynamics (MD) simulations accorded with the experimental findings. The MC simulation's assessment of CMEA's high adsorption energy (-185 Kcal/mol) proved that the CMEA efficiently and spontaneously adsorbs at the interface.

Green β-cyclodextrin-based corrosion inhibitors: Recent developments, innovations and future opportunities

β-Cyclodextrin-based compounds are used to develop and innovate materials that protect against corrosion due to their sustainability, low cost, environmental friendliness, excellent water solubility and high inhibition efficiency. However, corrosion potentials of β-CD-based compounds were not reviewed with the modern trends. The essence of the problem is that a deep understanding of the development and innovation of β-CD-based compounds as corrosion inhibitors is very important in creating next-generation materials for corrosion protection. In this review, the fundamental behaviour, importance, developments and innovations of β-CD modified with natural and synthetic polymers, β-CD grafted with the organic compounds, β-CD-based supramolecular (host-guest) systems with organic molecules, polymer β-CD-based supramolecular (host-guest) systems, β-CD-based graphene oxide materials, β-CD-based nanoparticle materials and β-CD-based nanocarriers as corrosion inhibitors for various metals were reviewed and discussed with recent research works as examples. In addition, the corrosion inhibition of β-CD-based compounds for biocorrosion, microbial corrosion and biofouling was reviewed. It was found that (i) these compounds are sustainable, inexpensive, environmentally friendly, and highly water-soluble and have high inhibition efficiency; (ii) the molecular structure of β-CD makes it an excellent molecular container for corrosion inhibitors compounds; (iii) the β-CD is excellent core to develop the next generation of corrosion inhibitors. It is recommended that (i) β-CD compounds would be synthesized by green methods, such as using biological sustainable catalysts and green solvents, green methods include irradiation or heating, energy-efficient microwave irradiation, mechanochemical mixing, solid-state reactions, hydrothermal reactions and multicomponent reactions; (ii) this review will be helpful in creating, enhancing and innovating the next green and efficient materials for future corrosion protection in high-impact industries.