Inhibition of cold rolled steel corrosion in sulphuric acid solution by 2-mercapto-1-methylimidazole: Time and temperature effects treatments

2-Mercapto-1-methylimidazole (MMI) has been evaluated as a corrosion inhibitor for cold rolled steel in aerated 2 M H₂SO₄ by gravimetric method. The effect of MMI on the corrosion rate was determined at various immersions time and concentrations. The effect of the temperature on the corrosion behaviour with addition of different concentrations of MMI was studied in the temperature range 30–60 °C. The MMI acts as an effective corrosion inhibitor for cold rolled in sulphuric acid medium. The inhibition process is attributed to the formation of an adsorbed film of MMI on the metal surface which protects the metal against corrosion. The protection efficiency increased with increase in inhibitor concentration at various immersions time and decreased with increase in temperature. Adsorption of MMI on the cold rolled steel surface is found to obey the Langmuir adsorption isotherm. Some thermodynamic functions of dissolution and adsorption processes were also determined.     

Electrochemical studies of mild steel corrosion inhibition in sulfuric acid chloride by aniline

The corrosion behavior of mild steel in dilute hydrochloric acid under the inhibiting action of various concentrations of aniline was studied using the weight loss and linear polarization resistance technique. The efficiency of the inhibitor increased with the increase in the inhibitor concentration. The results obtained reveal that aniline performed effectively as a corrosion inhibitor. The adsorption mechanism indicates mixed molecular interaction from values of Gibbs free energy. The values of the inhibition efficiency calculated from the two techniques are in reasonably good agreement. The adsorption of the inhibiting compound was found to obey Langmuir, Frumkin and Freudlich adsorption isotherms. The mechanism of inhibition was discussed in the light of the chemical structure of the inhibiting compound and their adsorption on steel surfaces in relation to the potentiodynamic parameters.     

Allylacetylenes and their derivatives as inhibitors of steel corrosion in sulfuric acid

New functionalized derivatives of allylacetylenes were prepared, and their ability to inhibit corrosion of St.3 low-carbon steel in 5 N sulfuric acid was studied. The effectiveness of inhibition of steel corrosion was studied in relation to the structure of acetylene derivatives, their concentration, and temperature of acidic medium.     

Inhibition of steel corrosion by calcium benzoate adsorption in nitrate solutions: theoretical and experimental approaches

The inhibitive effects of calcium benzoate on steel corrosion were studied in sodium nitrate solutions at room temperature. Corrosion parameters of the steel/nitrate and steel/benzoate + nitrate interfaces were obtained from polarization curves. Adsorption parameters of benzoate on steel in sodium nitrate solutions were determined through changes in the degree of surface coverage by the inhibitor, as a function of concentration, time, and adsorption potential. The most likely adsorption configuration of benzoate on iron was envisaged with the help of semiempirical calculations such as extended Hückel calculations. A two-dimensional flat configuration was involving at least two metal atoms, one interacting with the phenolic group and the other with the carboxylate moiety. The effect of chloride on the corrosion inhibition of benzoate was analyzed by exposing the metal to different chloride solution concentrations, from which corrosion parameters were calculated and compared with those in nitrate solutions.     

New Schiff base cationic surfactants as corrosion inhibitors for carbon steel in acidic medium: weight loss,electrochemical and SEM characterization techniques

Research on Chemical Intermediates - Two new Schiff base cationic surfactants were synthesized and their chemical structures confirmed using FTIR spectroscopy. The tensioactive and thermodynamic...     

红四氮唑在盐酸介质中对冷轧钢的缓蚀作用

用失重法、电化学法和原子力显微镜（AFM）研究了红四氮唑在1.0 mol/L ~ 5.0 mol/L HCl介质中对冷轧钢的缓蚀作用。结果表明：红四氮唑对冷轧钢具有良好的缓蚀作用,为混合抑制型缓蚀剂,且在钢表面的吸附符合Langmuir吸附模型;并通过吸附热力学和动力学参数详细讨论了缓蚀作用机理;AFM测试结果表明红四氮唑在钢表面吸附形成了致密的缓蚀剂膜层。     

Surface interaction and corrosion inhibition of carbon steel in sulfuric acid using Petroselinum crispum extract

With the aid of the mass loss (ML) method, and a few electrochemical techniques [potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS)], the inhibitory impact of Petroselinum crispum (PC) extract on C-steel corrosion in solutions of 1 M sulfuric acid was assessed. By employing Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) techniques, the C-steel surface morphology was investigated. The data showed that the solution of plant extract can be effectively utilized to inhibit C-steel corrosion in solutions of 1 M sulfuric acid. The effectiveness of the extract was enhanced by the higher extract dose and rising temperature. The apparent activation energy and the enthalpy of the dissolution process were determined and discussed. The presence of PC decreases the double-layer capacity from 493.1 to 107.3 μF cm⁻² and raises the charge transfer resistance in a solution of 1 M sulfuric acid from 43.39 to 287.7 Ω cm². PC is a mixed-type inhibitor, as demonstrated by PDP tests. The PC extract demonstrated the highest productivity for the C-steel protection up to 90.2% at 300 ppm from the extract, according with the PDP technique. The attained data indicated that PC extract was adsorbed chemically (ΔG^o_ads > 40 kJ mol⁻¹) onto the surface of the C-steel following the Temkin isotherm. The results of numerous tests appear to agree.     

O,O ′-二(苯基)二硫代磷酸-N,N-二乙铵对Q235钢硫酸溶液中的缓蚀性能研究

合成了O,O′-二(苯基)二硫代磷酸-N,N-二乙铵(DEDDP),采用失重,电化学和SEM技术共同研究了DEDDP在H2SO4溶液中对Q235钢的缓蚀性能.失重法研究表明:DEDDP在H2SO4溶液中能有效地抑制Q235钢腐蚀,25C的5％H2sO4溶液中,DEDDP浓度为160 mg ·L-1时,其缓蚀率为94.6...     

Inhibition of acid corrosion of mild steel by Anacyclus pyrethrum L. extracts

Inhibition of the corrosion of mild steel in sulfuric acid by extracts of Anacyclus pyrethrum L. (leaves and stems, AP-LS; flowers AP-F; roots, AP-R) has been studied by use of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Anacyclus pyrethrum L. inhibited the corrosion of mild steel in 0.5 M H₂SO₄ solution. Polarization curves show that the different parts of plants act as anodic type inhibitors. Changes in impedance data (charge transfer resistance, R _t, and double layer capacitance, C _dl) were indicative of adsorption of the extracts on the metal surface, leading to the formation of protective films. The extent of surface coverage by the inhibitors was determined by measurement of ac impedance; it was found that adsorption of these inhibitors on the mild steel surface obeys the Langmuir adsorption isotherm. Activation energies in the presence and absence of AP-LS and AP-F were obtained by measuring the temperature dependence of the corrosion current.     

Synergistic effect of polyethylene glycols and rare earth Ce4+ on the corrosion inhibition of carbon steel in sulfuric acid solution: electrochemical,computational, and surface morphology studies

Research on Chemical Intermediates - The inhibition effect of two selected polyethylene glycols (PEGs) with different molecular weight and the synergistic effect with rare earth Ce4+ ions on...     

Inhibition effect of butan-1-ol on the corrosion behavior of austenitic stainless steel (Type 304) in dilute sulfuric acid

The electrochemical behavior of austenitic stainless steel (Type 304) in 3 M sulfuric acid with 3.5% recrystallized sodium chloride at specific concentrations of butan-1-ol was investigated with the aid of potentiodynamic polarization, open circuit measurement and weight loss technique. Butan-1-ol effectively inhibited the steel corrosion with a maximum inhibition efficiency of 78.7% from weight-loss analysis and 80.9% from potentiodynamic polarization test at highest concentration studied. Adsorption of the compound obeyed the Freundlich isotherm. Thermodynamic calculations reveal physiochemical interactions and spontaneous adsorption mechanism. Surface characterizations showed the absence of corrosion products and topographic modifications of the steel. Statistical analysis depicts the overwhelming influence and statistical significance of inhibitor concentration on the inhibition performance.     

Inhibition of copper corrosion by arylazotriazoles in nitric acid solution

Summary A study has been made to investigate the effect of some azoheterocyclic dyes of the type 3-arylazo 1,2,4-triazole (AT) on the corrosion of copper exposed to 0.5M nitric acid solution at different temperatures and at differentAT concentrations. Using potentiodynamic polarization andTafel electrochemical methods, it can be shown thatAT compounds are good inhibitors of copper corrosion in HNO₃ solution. The kinetic and thermodynamic parameters of the inhibited system were determined. The high inhibition efficiency of these compounds may be due to the adsorption of the additive itself and/or the adsorption of the formed Cu(II)-AT complexes at the polarized electrode interface. Cathodic polarization measurements showed thatAT dyes are predominantly cationic inhibitors.

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Hemmung der Korrosion von Kupfer in salpetersaurer Lösung durch Arylazotriazole

Zusammenfassung Der Effekt einiger azoheterocyclischer Farbstoffe des Typs 3-Arylazo-1,2,4-triazol (AT) auf die Korrosion von Kupfer in 0.5M Salpetersäure bei verschiedenen Temperaturen und unterschiedlichenAT-Konzentrationen wurde untersucht. Potentiodynamische Polarisation und elektrochemische Methoden nachTafel zeigen, daß Verbindungen vom TypAT gute Korrosionsinhibitoren für Kupfer gegenüber HNO₃ sind. Die kinetischen und thermodynamischen Parameter des inhibierten Systems wurden bestimmt. Die hohe inhibitorische Wirksamkeit der untersuchten Verbindungen kann auf die Adsorption des Additivs selbst oder auf jene des Cu(II)-AT-Komplexes an der polarisierten Elektrodenoberfläche zurückzuführen sein. Kathodenpolarisationsmessungen zeigen, daßAT-Farbstoffe vorwiegend kationische Inhibitoren sind.

     

Some natural aqueous extracts of plants as green inhibitor for carbon steel corrosion in 0.5 M sulfuric acid

The inhibiting impact of natural aqueous extracts of some plants such as curcumin, parsley and cassia bark extracts for the corrosion of carbon steel (C-steel) in 0.5 M H₂SO₄ solution was inspected utilizing some techniques such as galvanostatic and potentiodynamic anodic polarization and weight loss measurements. Outcomes indicated that the percentage inhibition efficiency increases with increasing the concentration of the extract due to its horizontal adsorption on the C-steel surface. The process of adsorption is followed by the Temkin isotherm. These natural extracts acted as pitting corrosion inhibitors by shifting the pitting potential to more noble values. The sequence of inhibition efficiency of the natural extracts decreases in the following order: cassia bark extract > parsley extract > curcumin extract. This arrangement is related to the molecular size of the major components of the three natural extracts used.     

Microbiologically influenced corrosion of 304 stainless steel by aerobic Pseudomonas NCIMB 2021 bacteria: AFM and XPS study

Microbiologically influenced corrosion (MIC) of stainless steel 304 by a marine aerobic Pseudomonas bacterium in a seawater-based medium was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). AFM was used to observe in situ the proliferation of a sessile Pseudomonas cell by binary fission. The development of a biofilm on the coupon surface and the extent of corrosion damage beneath the biofilm after various exposure times were also characterized by AFM. Results showed that the biofilm formed on the coupon surface increased in thickness and heterogeneity with time, and thus resulting in the occurrence of extensive micro-pitting corrosion; whilst the depth of pits increased linearly with time. The XPS results confirmed that the colonization of Pseudomonas bacteria on the coupon surface induced subtle changes in the alloy elemental composition in the outermost layer of surface films. The most significant feature resulting from microbial colonization on the coupon surface was the depletion of iron (Fe) and the enrichment of chromium (Cr) content as compared to a control coupon exposed to the sterile medium, and the enrichment of Cr increased with time. These compositional changes in the main alloying elements may be correlated with the occurrence of extensive micropitting corrosion on the surface.     

Ni2+ cation and imidazole as corrosion inhibitors for carbon steel in sulfuric acid solutions

Abstract  

The effect of Ni²⁺ cation, imidazole, and mixtures of them on the corrosion behavior of carbon steel in 0.5 M H₂SO₄ solution was studied by using galvanostatic polarization, potentiodynamic anodic polarization, and weight-loss techniques. Ni²⁺ cation, imidazole, and mixtures of them provide a good protection to carbon steel against pitting corrosion in chloride-containing solutions. The inhibiting solutions were analyzed by using UV–Vis spectrophotometry. The inhibition was explained on the basis of formation of a complex between the two components. The inhibition mechanism was discussed in terms of the results derived from corrosion and UV–Vis spectrophotometric measurements as well as conductometric investigations.     

Green synthesis,electrochemical, and DFT studies on the corrosion inhibition of steel by some novel triazole Schiff base derivatives in hydrochloric acid solution

In this work, three triazole Schiff base derivatives 1-((1H-1,2,4-triazol-3-ylimino)methyl)naphthalen-2-ol (TMN), N-(furan-2-ylmethylene)-1H-1,2,4-triazol-3-amine (FTA) and N-(thiophen-2-ylmethylene)-1H-1,2,4-triazol-3-amine (TTA) were synthesized under ultrasonic irradiation and were investigated as corrosion inhibitors. FT-IR, NMR, and elemental analysis were used to elucidate the chemical structure of the synthesized inhibitors. The inhibitive characteristics of these inhibitors on C-steel corrosion in 1.0 M HCl were studied using three different techniques. The applied techniques were Electrochemical frequency modulation, electrochemical impedance spectroscopy, and potentiodynamic polarization curves. The acquired data from the experimental methods showed that the optimal concentration for TMN, FTA, and TTA is 1.0 × 10^?3 mol/L, and the inhibition efficiency reached up to 91.68%, 88.44%, and 87.29% for TMN, TTA, and FTA, respectively. Experiments also indicated that these compounds act as mixed-type inhibitors, and their concentration affects the inhibition efficiency in a directly proportional manner. Quantum paraments obtained from density functional theory (DFT) showed good agreement between experimental and computational results.     

A study on the electrochemical polymerization, characterization, and corrosion protection of o-toluidine on steel

Poly(o-toluidine) (POT) coatings were electrochemically synthesized on 304 stainless steel using cyclic voltammetric method. These coatings were characterized by Fourier transform infrared spectroscopy, UV–vis absorption spectroscopy, and cyclic voltammetry. The corrosion performance of POT coating in aqueous 3 wt% sodium chloride was assessed by the electrochemical techniques such as open circuit potential measurements, potentiodynamic polarization technique, cyclic potentiodynamic polarization measurements, and electrochemical impedance spectroscopy. The results reveal that POT coating on 304 stainless steel prevents general and localized corrosion, and reduces the exchange current density almost by a factor of 45 than bare 304 stainless steel.     

Surface characterization and electrochemical corrosion behaviour of 304 stainless steel in aqueous media

A formulation consisting 100 ppm of 3-phosphonopropionic acid, 50 ppm of Zn²⁺ and 150 ppm of Tween 80 (polyoxyethylene sorbitan monooleate) offered 97.4% inhibition to the corrosion of 304 austenitic stainless steel immersed in a groundwater environment. This formulation functioned as a mixed inhibitor. The protective film was analysed by luminescence, XRD and FTIR spectra and pit morphology and was also observed by scanning electron microscopy. Electronic Publication