Influence of tramadol [2-[(dimethylamino)methyl]-1-(3-methoxyphenyl) cyclohexanol hydrate] on corrosion inhibition of mild steel in acidic media

Organic Compounds as Corrosion Inhibitors for Carbon Steel in HCl Solution: A Comprehensive Review

Most studies on the corrosion inhibition performance of organic molecules and (nano)materials were conducted within “carbon steel/1.0 M HCl” solution system using similar experimental and theoretical methods. As such, the numerous research findings in this system are sufficient to conduct comparative studies to select the best-suited inhibitor type that generally refers to a type of inhibitor with low concentration/high inhibition efficiency, nontoxic properties, and a simple and cost-economic synthesis process. Before data collection, to help readers have a clear understanding of some crucial elements for the evaluation of corrosion inhibition performance, we introduced the mainstay of corrosion inhibitors studies involved, including the corrosion and inhibition mechanism of carbon steel/HCl solution systems, evaluation methods of corrosion inhibition efficiency, adsorption isotherm models, adsorption thermodynamic parameters QC calculations, MD/MC simulations, and the main characterization techniques used. In the classification and statistical analysis section, organic compounds or (nano)materials as corrosion inhibitors were classified into six types according to their molecular structural characteristics, molecular size, and compound source, including drug molecules, ionic liquids, surfactants, plant extracts, polymers, and polymeric nanoparticles. We outlined the important conclusions obtained from recent literature and listed the evaluation methods, characterization techniques, and contrastable experimental data of these types of inhibitors when used for carbon steel corrosion in 1.0 M HCl solution. Finally, statistical analysis was only performed based on these data from carbon steel/1.0 M HCl solution system, from which some conclusions can contribute to reducing the workload of the acquisition of useful information and provide some reference directions for the development of new corrosion inhibitors.

Effectiveness of some novel heterocyclic compounds as corrosion inhibitors for carbon steel in 1 M HCl using practical and theoretical methods

Corrosion of carbon steel is a major problem that destroys assists of industries and world steel installations; the importance of this work is to introduce new heterocyclic compounds as effective and low-cost corrosion inhibitors. Three compounds of carbohydrazide derivatives, namely: 5-amino-N'-((2-methoxynaphthalen-1-yl)methylene)isoxazole-4-carbohydrazide (H4), 2,4-diamino-N'-((2-methoxy-naphthalene-1-yl)methylene) pyrimidine-5-carbohydrazide (H5) and N'-((2-methoxynaphthalen-1-yl)methylene)-7,7-dimethyl-2,5-dioxo-4a,5,6,7,8,8a-hexahydro-2H-chromene-3-carbohydrazide (H6) were used to examine the efficacy of corrosion of carbon steel in 1 M hydrochloric acid solution. This corrosion efficacy was detected by utilizing various methods including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), weight loss measurements (WL), surface morphology analyses by atomic force microscopy (AFM), quantum chemical computations based on density functional theory (DFT) and molecular dynamics (MD) simulation. The results indicated that these compounds act as mixed type inhibitors i.e. reduce the corrosion rate of carbon steel due to the formation of a stable protective film on the metal surface and reduce the cathodic hydrogen evolution reaction. As confirmed from impedance, carbohydrazide derivatives molecules are adsorbed physically on metal surface with higher corrosion efficacy reached to (81.5-95.2%) at 20 × 10-6 M concentration at room temperature. Temkin isotherm model is the most acceptable one to describe the carbohydrazide derivative molecules adsorption on the surface of carbon steel. Protection mechanism was supported by quantum chemical analyses and Monte Carlo modeling techniques. The theoretical calculations support the experimental results obtained. This proves the use of carbohydrazide derivatives as a very effective inhibitors against the corrosion of carbon steel in acidic media.

Quinine sulfate: a pharmaceutical product as effective corrosion inhibitor for carbon steel in hydrochloric acid solution

Quinine sulfate dihydrate (QNS), IUPAC name: (8S,9R)-6-methoxy-4-quinolenyl-5-vinyl-2-quinuclidinyl methanol sulfate dihydrate, was tested as corrosion inhibitor for carbon steel in 1.5 mol L−1 HCl solution using the potentiodynamic polarization and the electrochemical impedance spectroscopy (EIS) associated with UV-Vis spectrophotometry. The electrochemical results showed that, the inhibition efficiency (IE) increased with the increase in QNS concentration, reaching a maximum value of 93.35±0.25%. The polarization resistance (R p) followed the same trend, obtaining the highest value of 659.7 Ω cm2, while the corrosion current density (i corr) reached the lowest level of 195 µA cm−2. The action mechanism of QNS was proposed considering the ability of quinine (QN) to be adsorbed on the metal surface via the lone pairs of electrons from hydroxyl oxygen atom, and/or from quinoline and quinuclidinic nitrogens. The occurrence of the complexes between inhibitor and iron ions was considered an additional process, which may contribute to protective layer formation. The Temkin adsorption isotherm was found as the best fitting for the degree of surface coverage (θ) values. In order to elucidate the mechanism of protective layer formation, the free energy of adsorption (ΔG o ads) value was calculated. This indicates that the inhibitor acts by chemical adsorption on the steel surface.

Corrosion Inhibition Effect of 4-Hydroxy-N′-[(E)-(1H-indole-2-ylmethylidene)] Benzohydrazide on Mild Steel in Hydrochloric Acid Solution

The inhibition performance and adsorption behaviour of 4-hydroxy-N′-[(E)-(1H-indole-2-ylmethylidene)] benzohydrazide (HIBH) on mild steel in 1 M HCl solution were tested by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The inhibition efficiency of HIBH increases with increase in inhibitor concentration in the temperature range 30–60°C. Polarisation curves indicate that HIBH is a mixed inhibitor, affecting both cathodic and anodic corrosion currents. The adsorption process of HIBH at the mild steel/hydrochloric acid solution interface obeyed Langmuir adsorption isotherm model and inhibition takes place by mixed adsorption, predominantly chemisorption. The activation and thermodynamic parameters for the corrosion inhibition process were calculated to elaborate the mechanism of corrosion inhibition.

Inhibition effects of a synthesized novel 4-aminoantipyrine derivative on the corrosion of mild steel in hydrochloric acid solution together with quantum chemical studies

1,5-Dimethyl-4-((2-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-one (DMPO) was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively) and dipole moment (μ) were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value.

A Novel Hydrazinecarbothioamide as a Potential Corrosion Inhibitor for Mild Steel in HCl

2-(1-methyl-4-((E)-(2-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-ylidene)-hydrazineecarbothioamide (HCB) was synthesized as a corrosion inhibitor from the reaction of 4-aminoantipyrine, thiosemicarbazide and 2-methylbenzaldehyde. The corrosion inhibitory effects of HCB on mild steel in 1.0 M HCl were investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results showed that HCB inhibited mild steel corrosion in acidic solution and inhibition efficiency increased with an increase in the concentration of the inhibitor. The inhibition efficiency was up to 96.5% at 5.0 mM. Changes in the impedance parameters suggested that HCB adsorbed on the surface of mild steel, leading to the formation of a protective film. The novel corrosion inhibitor synthesized in the present study was characterized using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectral data.

Inhibiting Effects of Rabeprazole Sulfide on the Corrosion of Mild Steel in Acidic Chloride Solution

The corrosion inhibition effect of Rabeprazole sulfide (RS) on mild steel in 1 M hydrochloric acid (HCl) was investigated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and chronoamperometric measurements. Protection efficiency of RS increases with the concentration and decreases with the rise in temperature. Adsorption of RS on mild steel surface in 1 M HCl follows Langmuir adsorption isotherm. The kinetic and thermodynamic parameters governing the adsorption process were calculated and discussed. The polarization results suggest that RS performed as an excellent mixed-type inhibitor for mild steel corrosion in 1 M HCl.

Aqueous Extract of Kalmegh (Andrographis paniculata) Leaves as Green Inhibitor for Mild Steel in Hydrochloric Acid Solution

The inhibition of the corrosion of mild steel in hydrochloric acid solution by the extract of Kalmegh (Andrographis paniculata) leaves extract has been studied using weight loss, electrochemical impedance spectroscopy, linear polarization, and potentiodynamic polarization techniques. Inhibition was found to increase with increasing concentration of the extract. The effect of temperature, immersion time, and acid concentration on the corrosion behavior of mild steel in 1 M HCl with addition of extract was also studied. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the metal surface. The adsorption of the molecules of the extract on the mild steel surface obeyed the Langmuir adsorption isotherm. The protective film formed on the metal surface was analyzed by FTIR spectroscopy. The results obtained showed that the extract of Kalmegh (Andrographis paniculata) leaves extract could serve as an effective inhibitor of the corrosion of mild steel in hydrochloric acid media.