Steel In Phosphoric Acid Research Articles

New Insights on the Corrosion–Erosion Behavior of 904L Stainless Steel in Phosphoric Acid Containing Impurities

New Insights on the Corrosion–Erosion Behavior of 904L Stainless Steel in Phosphoric Acid Containing Impurities

Development of Natural Plant Extracts as Sustainable Inhibitors for Efficient Protection of Mild Steel: Experimental and First-Principles Multi-Level Computational Methods.

In the present work, we present the superior corrosion inhibition properties of three plant-based products, Fraxinus excelsior (FEAE), Zingiber zerumbet (ZZAE), and Isatis tinctoria (ITAE), that efficiently inhibit the corrosion of mild steel in phosphoric acid. The anti-corrosion and adsorption characteristics were assessed using a combination of experimental and computational approaches. Weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy methods were used to evaluate the inhibitive performance of the inhibitors on the metal surface. Then, both DFT/DFTB calculations and molecular dynamic simulations were further adopted to investigate the interaction between organic inhibitor molecules and the metal surface. The protective layers assembled using the active constituents, such as carbonyl and hydroxyl groups, of the three plant-based products offer high electrochemical stability at high temperatures and robust protection against aggressive acidic solutions. All electrochemical measurements showed that the inhibition performance of extracts increased by increasing their concentration and improved in the following order: FEAE > ZZAE > ITAE. Further, these extracts worked as mixed-type inhibitors to block the anodic and cathodic active sites on the mild steel surface. Multi-level computational approaches revealed that FEAE is the most adsorbed inhibitor owing to its ability to provide electron lone pairs for electrophilic reactions. The experimental and theoretical results showed good agreement. These results indicate the possibility of replacing conventional compounds with natural substituted organic products in the fabrication of hybrid materials with effective anti-corrosion performance.

Experimental and theoretical studies of carbon steel corrosion protection in phosphoric acid solution by expired lansoprazole and rabeprazole drugs

The effects of expired lansoprazole and rabeprazole on the corrosion protection of carbon steel in phosphoric acid (3.0 ​M) solution were examined by Tafel polarization and electrochemical impedance spectroscopy (EIS). Lansoprazole and rabeprazole concentrations (0.5, 1.0, 5.0 and 10 ​mM) in acid solution were raised, which improved corrosion prevention. Both lansoprazole and rabeprazole as the mixed inhibitors retarded the anodic and cathodic processes, as indicated by polarization data. With the increasing temperature in the range of 25–55 ​°C, the inhibition efficiency drops from 92.9% to 69.3% for lansoprazole and from 94.8% to 74.2% for rabeprazole. The major decrease in the inhibition efficiency with ascending temperature proved the physisorption of the drugs. The activation energies for carbon steel corrosion in H3PO4solution were enhanced from 41.6 ​kJ ​mol−1 to 81.9 ​kJ.mol−1and 85.9 ​kJ ​mol−1 for lansoprazole and rabeprazole, respectively. The influence of temperature on the corrosion process of carbon steel in the acid medium was used to derive the thermodynamic quantities of corrosion. The adsorption of both lansoprazole and rabeprazole on carbon steel followed the Langmuir adsorption isotherm. The polarization data yielded outcomes that were consistent with the results arising from impedance measurements. The theoretical study of both lansoprazole and rabeprazole was done by a density functional theory (DFT) approach to realize the effects of molecular structure on their inhibitive action. Both lansoprazole and rabeprazole contain a higher EHOMO, a lower ELUMO and a lower energy gap than some inhibitors earlier reported as good corrosion inhibitors in the literature.

Theoretical Evaluation of the Corrosion Inhibition Performance of an Organic Heterocyclic Compound

The corrosion inhibition performance of a corrosion inhibitor on mild steel in phosphoric acid, namely 5-chloro-1-(2-(dimethylamino) ethyl) indoline-2,3-dione (TZCDI), was theoretically evaluated using density functional theory (DFT) at the B3LYP/6-31G+(d,p) level for all atoms by Gaussian 09W program. The quantum chemical properties, such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO) energy gap (∆Egap), dipole moment (μ), total hardness (η), and electronegativity (χ), were studied, and these descriptors were discussed in connection to the experimental inhibitory efficiency. The local reactivity was analyzed through the Fukui function in order to compare the possible sites for nucleophilic and electrophilic attacks. Accordingly, all data obtained using various theoretical calculation techniques were consistent with experiments.

Electrochemical, surface and computational studies on the inhibition performance of some newly synthesized 8-hydroxyquinoline derivatives containing benzimidazole moiety against the corrosion of carbon steel in phosphoric acid environment

Four new 8-hydroxyquinoline derivatives, namely 5-((1H-benzimidazol-2-yl)methyl)quinolin-8-ol (BIMQ), 5-((5-methyl-1H-benzimidazol-2-yl)methyl)quinolin-8-ol (MBMQ), 5-((5-chloro-1H-benzimidazol-2-yl)methyl)quinolin-8-ol (CBMQ) and 5-((5,6-dichloro-1H-benzimidazol-2-yl)methyl)quinolin-8-ol (DCBMQ) were prepared in moderate to good yields through the condensation of 5-(carboxymethyl)-8-hydroxyquinoline and substituted o-phenylenediamine. 1H, 13C NMR and elemental analysis confirm the formation of the desired compounds. The anti-corrosive potential of these heterocyclic compounds has been studied on carbon steel in 2M phosphoric acid (H3PO4) electrolyte by means of electrochemical measurements. The inhibition efficiency of these heterocyclic compounds was strongly linked to the concentration and the structure of the molecules; reached a maximum of 94.7% for DCBMQ at 10−3M. Data generated from potentiodynamic revealed that the investigated 8-hydroxyquinoline derivatives are mixed type inhibitors. The influence of temperature on the corrosion behaviour was assessed. The four quinoline derivatives adsorbed according to the Langmuir's adsorption isotherm. Surface analysis (SEM and XPS) confirmed the formation of a protective layer adsorbed on the steel surface. DFT calculations suggested that 8-hydroxyquinoline derivatives adsorb on the metal via the 8-hydroxyquinoline ring and their corrosion inhibition potential have some linear correlation with the degree of co-planarity of the benzimidazole and hydroxyquinoline rings. Monte Carlo simulations showed that the molecules adsorbed on Fe(110) surface through the 8-hydroxyquinoline in a near-flat mode and the adsorption energies both in the absence and presence of aqueous phosphate ions agree with the observed trends of inhibition efficiencies.

Green approach to corrosion inhibition of stainless steel in phosphoric acid of Artemesia herba albamedium using plant extract

Essential oil from aerial parts of Artemisia herba-alba from Morocco was hydrodistilled and its chemical composition oil was investigated by capillary GC and GC/MS. The major components were 1,8-cineole (35.6%) and camphor (24.1%). Artemisia herba-alba essential oil AHAO was tested as corrosion inhibitor of stainless steel (SS) in 1M H3PO4 using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy measurements (EIS) and scanning electronically microscopy (SEM) studies. The results obtained showed that the essential oil of Artemisia reduces the corrosion rate. Tafel polarization method indicates that the plant extract behaves as a mixed type inhibitor. The inhibition efficiency increased with inhibitor concentration to attain 88% at 1g.L−1 of oil at 298K. Nyquist diagrams obtained from impedance studies provide results confirming the anti-corrosion effect of the studied plant. The temperature effect on the corrosion behavior of (SS) in 1M H3PO4 without and with AHAO at 1g.L−1 was studied in the temperature range from 298 to 353K. Thermodynamic parameters suggested that the adsorption is spontaneous and exothermic process and support physical adsorption mechanism. The experimental data fits well into the Langmuir adsorption isotherm model. SEM/EDS studies provide the confirmatory evidence for the protection of (SS) by the green inhibitor. The results obtained from these methods used are in good agreement.

Electropolishing of steel in presence of some amines

Electropolishing of Steel in phosphoric acid is considered as corrosion rate of Steel and due to the economic importance of Steel, there are several researches deals with acceleration and inhibition of this process. This paper threw some light on the effect of adding some organic amines on the electropolishing of steel. Different concentration were used from 10−5mol.L-1 to 10-2 mol.l-1 and different organic amines derivatives (methyl amine, dimethyl amine, diethyl amine, triethyl amine, diethanol amine and triethanol amine) were used. Electropolishing process of steel inhibited by different ratio. The results show that organic amines have strongest inhibiting effect ranging from 5% to 59.7% and the thermodynamic parameters as ΔS*, ΔH* and ΔG* were studied. The values of ΔGads are given in negative values in all cases means that spontaneous adsorption of inhibitor on steel surface and strong interaction between the inhibitor molecules and metal surface. It lies in the range of (32–38) kJmol-1 for Flory - Huggins and (15–17) KJ mol-1 for kinetic isotherm. It's found that (ΔGads) values are more positive than -40 Kjmol-1 indicating that the inhibitors are physically adsorbed on the metal surface and the adsorption isotherm were given. The effect of amines compounds with nitrogen free, on the corrosion process is revealed by adsorption curves. The efficiency in inhibition decreases in the order: triethanol amine > diethanol amine > triethyl amine > diethyl amine > dimethyl amine > methyl amine.

Synergistic Effect of Iodide Ion and Methyl Violet on the Corrosion Inhibition of Carbon Steel in Phosphoric Acid

Synergistic Effect of Iodide Ion and Methyl Violet on the Corrosion Inhibition of Carbon Steel in Phosphoric Acid

Thiourea and N-Methylthiourea as Corrosion Inhibitors for Steel in Phosphoric Acid

The effect of thiourea (TU) and N-methylthiourea (MTU) on the corrosion of mild steel in 0.5 M H3PO4 was examined using potentiodynamic polarization curve measurements, electrochemical impedance spectroscopy techniques and quantum chemical calculations. Results obtained revealed that MTU is more effective than TU in 0.5 M H3PO4. Theoretical fitting of different adsorption isotherms such as Langmuir, Flory–Huggins, Temkin, and the kinetic-thermodynamic models was tested. The thermodynamic activation parameters were calculated. Quantum chemical parameters were calculated and explained. The data explained that the inhibition of mild steel by TU in 0.5 M H3PO4 take place through chemical adsorption mechanism, while physicochemical adsorption mechanism is suggested for MTU.

Corrosion inhibition of steel in phosphoric acid

AbstractPhosphoric acid has been used in many industrial applications and can be in contact with a lot chemical and petrochemical equipment. Most of this equipment is made of steel alloys that may be damaged because of contact with acid. Corrosion inhibitors can be used for to protect steel alloys against several forms and various environments of corrosion. In this paper, the efficiency and applications of organic and inorganic inhibitors in different environments of phosphoric acid are investigated. More than 40 papers were collected and reviewed. Surveys of the stated works in phosphoric acid environments are documented. It was concluded that organic inhibitors performed as good corrosion inhibitors and are used widely. The use of inorganic inhibitors was limited. Most of studied inhibitors follow Langmuir’s adsorption isotherm, and the mechanism of the inhibition can be ascribed to the mixed effect on cathodic and anodic reactions. The synergistic effect was also addressed in the present work.

Potential of borage flowers aqueous extract, Borago officinalis L., against the corrosion of mild steel in phosphoric acid

PurposeThis paper aims to evaluate the inhibitive potential of borage flowers’ aqueous extract (BFAE), Borago officinalis L., against the corrosion of mild steel in 1.0 M phosphoric acid.Design/methodology/approachEvaluation was carried out by chemical hydrogen evolution (HE), mass loss (ML) and electrochemical potentiodynamic polarization (PDP) measurements. SEM-EDX analysis also was used to confirm the existence of the adsorbed film.FindingsIt was found that the inhibition efficiency of BFAE increases with the increase in its concentration, but decreases with the increase in temperature. The potentiodynamic polarization curves indicated that BFAE acts as a mixed-type inhibitor with a predominantly anodic action. The adsorption of BFAE on mild steel surface was found to obey Langmuir and thermodynamic-kinetic adsorption isotherms by forming a thin film on the metal surface. SEM-EDX analysis confirms the corrosion inhibition ability of BFEA in 1.0 M H3PO4 by forming a thin film on mild steel surface. In this study, the inhibitive action of BFAE components is discussed on the basis of the physical adsorption mechanism. The same results were obtained for both the freshly prepared extract and the one that kept in a refrigerator for one year.Originality/valueThis paper indicates that BFAE can act as a good inhibitor for the corrosion of mild steel in 1.0 M H3PO4 even after one year of preparation.

Modelling and Optimization of Corrosion Inhibition of Mild Steel in Phosphoric Acid by Red Pomegranate Peels Aqueous Extract

Taguchi experimental design (TED) is applied to find the optimum effectiveness of aqueous Red Pomegranate Peel (RPP) extract as a green inhibitor for the corrosion of mild steel in 2M H3PO4 solution. The Taguchi methodology has been used to study the effects of changing, temperature, RPP concentration and contact period, at three levels. Weight-loss measurements were designed by construction a L9 orthogonal arrangement of experiments. Results of the efficiencies of inhibition were embraced for the signal to noise proportion & investigation of variance (ANOVA). The results were further processed with a MINITAB-17 software package to find the optimal conditions for inhibitor usage. Second order polynomial model was used for experimental data fitting. Optimum conditions for achieving the maximum corrosion inhibition efficiency are obtained from optimizing the above model and are found as follow: 39.66 °C temperature of acidic media, 38.29 ml/L inhibitor concentration and 2.95 h contact period. Results demonstrated that rate of corrosion was increased with temperature increasing & decreasing inhibitor concentration. It was concluded that the Taguchi design was adequately useful in the optimization of operating parameters and that RPP sufficiently inhibited the corrosion of steel at the range of variables studied.

Testing and Comparing the Inhibitory Action of Red Onion Seeds and Peels Extracts on the Corrosion of Steel in Phosphoric Acid

The inhibitory action of Red onion seeds and peels extracts (ROSE & ROPE) was testing and comparing on the corrosion of steel in 0.75 M H3PO4 using chemical measurements (hydrogen evolution, HE and mass loss, ML) and SEM technique. The effect of temperature on the corrosion of steel in 0.75 M H3PO4 without and with certain concentration of each extract was studied in the temperature range of 303-333 K. Generally, the inhibition efficiency (i.e. surface coverage) increases with extracts concentration and fits the Langmuir adsorption isotherm. The results of HE, ML and SEM showed that ROSE has a capability to protect steel surface in 0.75 M H3PO4 more than ROPE. Good agreement between HE and ML measurements was obtained. Temperature coefficients without and with each extract revealed somewhat chemisorptive and physiosorptive behavior of ROSE and ROPE, respectively. Good correlation between the major effective constituents of each extract and the inhibition mechanism was obtained.

Novel cationic surfactant based on triazole as a corrosion inhibitor for carbon steel in phosphoric acid produced by dihydrate wet process

The corrosion inhibition effect of novel cationic surfactant based on tolyltriazole on carbon steel in 7M H3PO4 solution has been evaluated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) methods. The inhibition efficiency increases with increasing inhibitor concentration, but it decreases with increasing the temperature. The adsorption of inhibitor is mixed physical and chemical adsorption and found to obey the Langmuir adsorption isotherm. Data obtained from EIS studies were analyzed to model inhibition process through appropriate equivalent circuit model. Potentiodynamic polarization studies have shown that the inhibitor acts as a mixed type of inhibitor. Scanning Electron Microscopy (SEM) study also confirmed the protection of the metal surface by the used cationic surfactant.

Psidium Guajava Leaf Extract as Green Corrosion Inhibitor for Mild steel in Phosphoric Acid

Psidium Guajava Leaf Extract as Green Corrosion Inhibitor for Mild steel in Phosphoric Acid

Evaluation of Benzyl Triphenyl Phosphonium Chloride as Corrosion Inhibitor for Mild Steel in Phosphoric Acid

Evaluation of Benzyl Triphenyl Phosphonium Chloride as Corrosion Inhibitor for Mild Steel in Phosphoric Acid

Effect of Temperature on Electrochemical Behavior of Stainless Steel in Phosphoric Acid

Electrochemical behavior of 304L and S32304 stainless steel in different temperature and concentration phosphoric acid solution by means of polarization curve and electrochemical impedance spectroscopy. The results showed that with the increase of the phosphoric acid solution temperature, the corrosion voltage and the corrosion current of the stainless steel increase and the polarization resistance and solution resistance decrease. The corrosion-resistant properties of S32304 stainless steel are superior to that of 304L stainless steel.

Apricot juice as green corrosion inhibitor of mild steel in phosphoric acid

The corrosion protection of mild steel in 1M H3PO4 solution by apricot juice was studied at different temperatures by weight loss technique. Adsorption, activation and statistical studies were addressed in this work. Adsorption studies showed that inhibitor adsorbed on metal surface according to Langmuir isotherm. Average value of heat of adsorption was −14.93kJ/mol indicates a spontaneous physical adsorption on metal surface. Activation parameters did not changed with addition of inhibitor indicates that there is no change in reaction mechanism. Analysis of variance (ANOVA) was also applied. This analysis showed that the corrosion rate influenced by temperature, inhibitor concentration and combined interaction of them.

Studies on the inhibitive effect of potassium ferrocyanide on the corrosion of steel in phosphoric acid

In this work, the effect of potassium ferrocyanide (Pf) on the corrosion of mild steel in solutions of phosphoric acid (H3PO4) has been investigated in relation to the concentration of the inhibitor by weight loss, potentiodynamic polarization and AC impedance (EIS) measurements. The results obtained revealed that this compound is good a mixed-type inhibitor. The effect of temperature on the corrosion behavior with the addition of optimal concentration of Pf was studied in the temperature range 298–328 K. The value of inhibition efficiency decreases slightly with the increase in temperature. Changes in impedance parameters (charge transfer resistance, R t, and double layer capacitance, C dl) were indicative of adsorption of Pf on the metal surface, leading to the formation of a protective film. Adsorption of Pf on the C38 steel surface was found to obey the Langmuir adsorption isotherm. Some thermodynamic functions of dissolution and adsorption processes were also determined.

Corrosion control of carbon steel in phosphoric acid by purpald – Weight loss, electrochemical and XPS studies

The corrosion inhibition properties of purpald (4-amino-3-hydrazino-5-mercapto-1,2,4-triazole (AHMT)) on carbon steel in phosphoric acid (2M H3PO4) solution has been examined and characterized by weight loss, Tafel polarization, electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) methods. The experimental results reveal that the compound has a good inhibiting effect on the carbon steel in 2M H3PO4 solution. The protection efficiency increases with increasing inhibitor concentration, but the temperature has hardly effect on the inhibition efficiency of AHMT. The adsorption of AHMT is found to obey the Langmuir adsorption isotherm. Thermodynamic data and XPS analysis clearly show that the adsorption mechanism of AHMT on carbon steel surface in 2M H3PO4 solution is mainly electrostatic-adsorption. Potentiodynamic polarization studies have shown that AHMT acts as a mixed-type of inhibitor. Data obtained from EIS studies were analyzed to model inhibition process through appropriate equivalent circuit model.