Synthesis, Surface Properties, Synergism Parameter and Inhibitive Performance of Novel Cationic Gemini Surfactant on Carbon Steel Corrosion in 1 M HCl Solution

Electrochemical and gravimetric measurements were performed to investigate the effectiveness of a synthesized cationic gemini surfactant as corrosion inhibitor for carbon steel in 1 M HCl solution. The inhibition efficiency obtained from all methods are in good agreement. Potentiodynamic polarization measurements showed that, the prepared surfactant hinders both anodic and cathodic processes, i.e. acted as mixed-type inhibitor. It was found that the adsorption of the synthesized inhibitor followed the Langmuir adsorption isotherm and showed a mixed physical and chemical adsorption. Kinetic parameters were calculated and discussed. The inhibitor exhibited a synergistic effect with Sn²⁺ more than with Cu²⁺. The synthesized cationic gemini surfactant exhibited good surface properties.     

A Corrosion Inhibition Study of a Novel Synthesized Gemini Nonionic Surfactant for Carbon Steel in 1 M HCl Solution

In this study, a gemini nonionic surfactant was synthesized as a corrosion inhibitor for carbon steel in 1 M HCl. Surface properties of the synthesized gemini nonionic surfactant were determined by using surface tension. The results showed that the gemini nonionic surfactant has good surface active properties. The corrosion inhibition effect of the synthesized inhibitor on carbon steel was evaluated by using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and weight loss methods. The characterization of the film formed on the steel surface was carried out by scanning electron microscope (SEM) methods. The inhibitor molecules were adsorbed physically onto a carbon steel surface according to the Langmuir adsorption isotherm. The results revealed that the inhibitor acted as a mixed-type inhibitor. It was found that the inhibition efficiency increases with an increase in inhibitor concentration and decreases with increasing temperature. Thermodynamic parameters were calculated to elucidate the inhibitive mechanism.     

Gemini型表面活性剂在HCl溶液中的缓蚀性能研究

利用静态失重法和动态电化学方法对gemini型季铵盐缓蚀剂C10-4-C10,C12-4-C12,C14-4-C14和C16-4-C16在1mol/L HCl介质中对45#钢片的缓蚀性能进行了研究,结果表明,在1mol/L的HCl溶液中,gemini型季铵盐缓蚀剂在45#钢片表面上形成单分子层吸附,对45#钢片有优异的缓蚀性能,缓蚀率随缓蚀剂浓度增加而升高;极化曲线表明,gemini型季铵盐缓蚀剂在HCl溶液中是以抑制阴极过程为主的阴极型缓蚀剂。     

Synthesis and Inhibition Effect of a Novel Tri-cationic Surfactant on Carbon Steel Corrosion in 0.5 M H2SO4 Solution

A novel Tri-cationic surfactant was synthesized, purified and characterized. The critical micelle concentration value of the prepared surfactant was determined by surface tension and conductivity measurements. The surface parameters were calculated by surface tension measurements. The relationship between the surface properties and the corrosion inhibition efficiency of the prepared surfactant was discussed. The inhibition effect of the novel Tri-cationic surfactant on carbon steel corrosion in 0.5 M H₂SO₄ was studied by potentiodynamic polarization, electrochemical impedance spectroscopy and weight loss techniques. Potentiodynamic polarization studies revealed that the inhibitor acted as a mixed-type inhibitor. The high inhibition efficiency was attributed to the blocking of active sites on the steel surface through the adsorption of inhibitor molecules. Inhibitor adsorption on the carbon steel surface was in accordance with the Langmuir adsorption isotherm model. Thermodynamic adsorption and kinetic parameters were obtained from weight losses at different temperatures (20–60 °C).     

[BMIM]BF4 ionic liquids as effective inhibitor for carbon steel in alkaline chloride solution

The inhibition action of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF₄) ionic liquids towards carbon steel corrosion in alkaline chloride solution was investigated by electrochemical measurements. The morphology of the surface was examined by atomic force microscopy (AFM), and the surface composition was evaluated via X-ray photoelectron spectroscopy (XPS) as well in order to verify the presence of inhibitor on the carbon steel surface. The results showed that the compound effectively suppressed both cathodic and anodic processes of carbon steel corrosion in alkaline solution by multi-center adsorption on carbon steel surface according to Langmuir adsorption isotherm, and acted as a mixed type inhibitor. The inhibition mechanism was proposed based on the viewpoint of complex physic-chemical interactions between the cationic inhibitor molecule and the carbon steel surface.     

Corrosion Inhibition Efficiency,Electrochemical and Quantum Chemical Studies of Some New Nonionic Surfactants for Carbon Steel in Acidic Media

In this work, three types of nonionic surfactant as corrosion inhibitors were synthesized. The chemical structure of the prepared inhibitors was confirmed using FT‐IR and ¹H‐NMR spectroscopy. The surface tension and thermodynamic properties of these inhibitors were investigated. The corrosion inhibition efficiency of these surfactants was investigated on a carbon steel surface in 1 M HCl solution by weight loss and electrochemical measurements. Untreated and treated steel surfaces were characterized by scanning electron microscopy. Results show that the inhibition efficiency of the prepared inhibitors increases with increasing the ethylene oxide units. Also, the potentiodynamic polarization curves indicated that the investigated inhibitors behave as a mixed type inhibitor. Adsorption of these surfactants on the carbon steel surface was found to obey Langmuir's adsorption isotherm. The computed quantum chemical properties viz., electron affinity (EA), highest occupied molecular orbital (E_HOMO), the lowest unoccupied molecular orbital (E_LUMO), energy gap ΔE = E_HOMO ? E_LUMO, dipole moment (μ), polarizability and total energy (E_T) show good correlation with experimental inhibition efficiency.     

Synergistic inhibition between the gemini surfactant and bromide ion for steel corrosion in sulphuric acid

The inhibitive synergistic effect between a cationic gemini surfactant, 1,3-propane-bis(dimethyl dodecylammonium bromide) (12-3-12), and bromide ion for the corrosion inhibition of cold rolled steel in 0.5 mol L⁻¹ H₂SO₄ was investigated by weight loss, potentiodynamic polarization method and electrochemical impedance spectroscopy (EIS). The inhibition system composed by 12-3-12 and bromide ion is efficient. The adsorption mechanism of the 12-3-12 and bromide ion on steel in acidic medium is discussed on the basis of experimental data and an adsorption model is proposed. Adsorption of inhibitor system on the mild steel surface in acidic medium obeys Langmuir’s adsorption isotherm. In addition, potentiodynamic polarization studies show that the system acts as a mixed-type inhibitor. Electrochemical impedance spectroscopy also suggests the formation of a protective layer on the steel surface by the adsorption of surfactant molecules and bromide ions.     

Silybum marianum extract as a natural source inhibitor for 304 stainless steel corrosion in 1.0 M HCl

The use of Silybum marianum leaves extract as a 304 stainless steel corrosion inhibitor in 1.0 M HCl solution was investigated by weight loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. Potentiodynamic polarization curves indicated that S. marianum extract behaves as mixed-type inhibitor. The adsorption of the extract constituents was further discussed in view of Langmuir adsorption isotherm. The effect of temperature on the inhibition efficiency was studied. Quantum chemical parameters were also calculated, which provided reasonable theoretical explanation for the adsorption and inhibition behavior of S. marianum extract on the 304 stainless steel.     

Inhibition of acid corrosion of steel using cetylpyridinium chloride

The cationic surfactant cetylpyridinium chloride (CPC) showed high inhibition efficiency for the corrosion of low carbon steel in 1 M H₂SO₄. Electrochemical measurements were dedicated to test the performance of CPC at different concentrations and temperatures. CPC has a significant inhibiting effect on the corrosion of steel and protection efficiencies up to 97% were measured. The inhibitor shifted the corrosion potential in the cathodic direction. It was found that adsorption is consistent with the Bockris–Swinkels isotherm in the studied temperature range (30–60 °C). The negative values of the free energy of adsorption and the decrease in apparent activation energy in the presence of the inhibitor suggest chemisorption of the CPC molecule on the steel surface.     

Bio-/Environment-Friendly Cationic Gemini Surfactant as Novel Corrosion Inhibitor for Mild Steel in 1 M HCl Solution

Bio-/environment-friendly cationic gemini surfactant, ethane-1,2-diyl bis(N,N-dimethyl-N-hexadecylammoniumacetoxy)dichloride, referred to as 16-E2-16, was synthesized and characterized. Corrosion inhibition effects of 16-E2-16 on mild steel (MS) surface in 1 M HCl solution at 30, 40, 50 and 60 °C were evaluated using gravimetric analysis, potentiodynamic polarisation and electrochemical impedance spectroscopy measurements. The nature of the protective inhibitor film formed on the MS surface was analysed by SEM, EDAX and FT-IR, while TGA was used to assure the thermal behaviour and stability of the film at high temperature. The formation of [inhibitor-Fe²⁺] on the surface of MS was confirmed by UV–visible spectroscopy. The inhibition efficiency of the studied inhibitor increased with increasing concentration and solution temperature. The compound behaved as a mixed type inhibitor and acted by blocking the electrode surface by means of adsorption obeying the Langmuir adsorption isotherm. Surface active properties and corrosion inhibition effects of 16-E2-16 in the presence of inorganic (NaI) and organic (NaSal) salts were also investigated and are discussed. Density functional theory calculations have been carried out to correlate the efficiency of the compound with its intrinsic molecular parameters.     

Cationic gemini surfactant as corrosion inhibitor for mild steel in 1 M HCl and synergistic effect of organic salt (sodium tosylate)

Synergistic result of cationic gemini surfactant (GS) 1,2-bis(N-hexadecyl-N,N-dimethylammonium) ethane dibromide (16-2-16) and organic salt (Sodium tosylate; NaTos) on mild steel corrosion in 1?M HCl solution at various temperatures (30, 40, 50 and 60?°C) has been examined using gravimetric, electrochemical and surface morphology measurement. Investigational result shows that the inhibition efficiency (η) of 16-2-16 GS enhanced in the existence of a set quantity of NaTos. The synergism parameter (S_θ) values are larger than unity, representing large inhibition efficiency, generated via the accumulation of NaTos to 16-2-16 GS is owing to adsorption supportive. The electrochemical results revealed that the 16-2-16 GS in the absence and presence of NaTos act as mixed-type inhibitors. The inhibitor adsorption on the mild steel surface in 1?M HCl solution obeys Langmuir adsorption isotherm. Surface morphology was studied using scanning electron microscopy (SEM).     

Eco friendly corrosion inhibitors: Inhibitive action of quinine for corrosion of low carbon steel in 1 m HCl

Quinine, a natural product, was investigated as a corrosion inhibitor for low carbon steel in 1.0 m HCl solution. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used to study the inhibition action in the temperature range 20–50 °C. The corrosion of steel was controlled by a charge transfer process at the prevailing conditions. The electrochemical results showed that quinine is an efficient inhibitor for low carbon steel and an efficiency up to 96% was obtained at 20 °C. The inhibition efficiency increases with inhibitor concentration and reaches a near constant value in the concentration range 0.48 mM and above. Application of the Langmuir adsorption isotherm enabled a study of the extent and the mode of adsorption.     

Corrosion Inhibition and Adsorption Behavior of Sodium Lauryl Ether Sulfate on L80 Carbon Steel in Acetic Acid Solution and Its Synergism with Ethanol

The application of sodium lauryl ether sulfate (SLES) as an anionic surfactant and its synergistic combination with ethanol for inhibition of corrosion of L80 carbon steel in acetic acid solutions were investigated by means of potentiodynamic polarization measurements, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray (EDX) investigations. The inhibition efficiency increases with an increase in concentration of SLES. The adsorption of SLES on the surface of L80 carbon steel obeys the Freundlich isotherm. SLES acts predominately as an anodic inhibitor. XRD, EDX, and SEM examinations of the electrode surface confirmed the adsorption of SLES on the electrode surface. The addition of ethanol with SLES significantly enhances the inhibition effectiveness and generates a strong synergistic effect.     

Understanding the inhibitory effect of sodium oleate on the corrosion of Al and Al–Cu alloys in 1.0 M H<Subscript>3</Subscript>PO<Subscript>4</Subscript> solution—Polarization studies

Polarization measurements were employed, as a first step towards studying the corrosion behaviour of Al and two Al–Cu alloys, namely Al–4.5%Cu, and Al–7.5%Cu alloys in deaerated stirred 1.0 M H₃PO₄ solution at 25 °C. Inhibition of Al and Al–Cu alloys corrosion in 1.0 M H₃PO₄ solution, using sodium oleate (SO) as an anionic surfactant inhibitor, was also studied. Polarization curves showed that SO acted as a mixed-type inhibitor to Al corrosion, while it acted mainly as a cathodic inhibitor to the acid corrosion of Al–4.5%Cu, and Al–7.5%Cu alloys. Inhibition is accomplished by inhibitor adsorption on the electrode surface without detectable changes in the chemistry of corrosion. The relationship between surfactant concentration, surfactant critical micellar concentration (CMC), and corrosion inhibition is also discussed based on the Langmuir isotherm assumption, commonly applied in corrosion inhibition evaluations. The protection efficiency increases with increase in surfactant concentration and %Cu in Al samples. Maximum protection efficiency of the surfactant is observed at concentrations around its CMC. The mechanism of adsorption is discussed based on the surface charge of the electrode surface.     

Comparison of a Cationic Gemini Surfactant and the Corresponding Monomeric Surfactant for Corrosion Protection of Mild Steel in Hydrochloric Acid

A cationic gemini surfactant, N,N′-didodecyl-N,N,N′,N′-tetramethyl-1,4-butanediammonium dibromide (12-4-12) and the corresponding monomeric surfactant dodecyltrimethylammonium bromide were compared with respect to corrosion inhibition efficiency in 1 M hydrochloric acid solution. Polarization and electrochemical impedance spectroscopy were used to evaluate corrosion inhibition. The 12-4-12 surfactant showed an extremely high corrosion inhibition efficiency at very low concentration. Surface tension measurements performed under the strongly acidic conditions revealed that the gemini surfactant is remarkably electrolyte tolerant, which is beneficial for adsorption at the steel surface.     

TAURINE AS A GREEN CORROSION INHIBITOR FOR AISI 4130 STEEL ALLOY IN HYDROCHLORIC ACID SOLUTION

The inhibition ability of 2-aminoethanesulfonic acid (taurine) against the corrosion of AISI steel 4130 in 1 M HCl solution was evaluated by polarization, impedance (EIS), and chronoamperometry. Polarization studies indicated that taurine retards both cathodic and anodic reactions through chemical adsorption and blocking the active corrosion sites. The adsorption of this compound obeyed the modified Langmuir adsorption isotherm. EIS data shows that as the inhibitor concentration increased, the charge transfer resistance of steel increased, while double layer capacitance decreased. Kinetic and thermodynamic parameters such as activation energy, enthalpy, entropy, and free energy of activation and adsorption were calculated. Gibbs free energy indicated that the adsorption process is spontaneous. Atomic force microscopy (AFM) and optical microscopy were used to study the steel surface. Surface studies show that the surface of a sample in solution with inhibitor molecules looks more uniform, with less roughness, than that in the uninhibited solution. Results obtained from quantum chemical studies show excellent correlations between quantum chemical parameters and experimental inhibition efficiencies using density functional theory (DFT).     

Evaluation of electrochemical frequency modulation as a new technique for monitoring corrosion and corrosion inhibition of carbon steel in perchloric acid using hydrazine carbodithioic acid derivatives

Electrochemical frequency modulation, EFM is a new technique for corrosion rate measurements. With the EFM technique, the corrosion rate and corrosion kinetic parameters can be obtained instantaneously without prior knowledge of Tafel slopes, which makes this method an ideal technique for application as a corrosion monitoring tool. Results obtained with the EFM technique were shown to be in agreement with chemical (weight loss) and electrochemical methods (Tafel extrapolation and electrochemical impedance spectroscopy, EIS) for corrosion rate measurements. New synthesized hydrazine carbodithioic acid derivatives namely, N′-furan-2-yl-methylene-hydrazine carbodithioic acid (A), N′-(4-dimethylamino-benzylidene)-hydrazine carbodithioic acid (B) and N′-(3-nitro-benzylidene)-hydrazine carbodithioic acid (C) were examined as corrosion inhibitors for carbon steel in 1 M perchloric acid solution. The results obtained from both chemical and electrochemical measurements show that these compounds suppressed both anodic and cathodic processes of carbon steel corrosion in 1 M HClO₄ by adsorption on the electrode surface. The adsorption mode follows the Langmuir adsorption isotherm. The efficiency of the inhibitors increases in the order C > B > A.     

表面活性剂在HCl中对钢的缓蚀协同效应

用失重法和电化学法研究了在1.0 mol/L HCl中阴离子表面活性剂油酸钠(SO)和非离子表面活性剂聚乙二醇辛基苯基醚(OP)对冷轧钢的缓蚀协同作用.研究结果表明,单独的SO和OP对冷轧钢具有一定的缓蚀作用,为混合型缓蚀剂,且在钢表面的吸附符合Temkin吸附模型.当两者复配后产生了明显的缓蚀协同效应,最大缓蚀率可达92%.     

Exploring deep insights into the interaction mechanism of a quinazoline derivative with mild steel in HCl: electrochemical,DFT, and molecular dynamic simulation studies

A novel quinazoline derivative, 3-cyclopropyl-3,4-dihydroquinoline-2(1H)-One (CPHQ), was successfully designed and synthesized. Then, its corrosion inhibition behavior on carbon steel (CS) surface in 1.0?M HCl at different temperatures was investigated using chemical, electrochemical and theoretical techniques. The experiments confirmed that the studied inhibitor shows inhibition efficiency as high as 95% even at very low concentration of 5?×?10^?3 M. To ascertain the nature of adsorption of CPHQ molecules on CS surface, Langmuir adsorption isotherm model was best fitted. From potentiodynamic polarization (PDP) calculations, it was concluded that the CPHQ acted as a mixed type corrosion inhibitor. Electrochemical impedance spectroscopy (EIS) studies revealed that increase in CPHQ concentration, resulted in an increase in the polarization resistance with a simultaneous decrease in the double-layer capacitance values. PDP tests were also performed to understand the corrosion behavior of CS as a function of temperature without and with varying concentrations of CPHQ, at temperatures 303, 313, 323, and 333?K. It can be concluded that the corrosion inhibition effect was dependent on the concentration of the inhibitor and the solution temperature. In order to understand the basic insights of the action mode of CPHQ molecules, Density Functional Theory (DFT) method, and Molecular Dynamic (MD) simulations were also employed on the optimized structure of CPHQ.     

双咪唑啉衍生物缓蚀剂的合成与缓蚀研究

以二乙撑三胺和己二腈原料合成了双咪唑啉BM,采用了失重法和极化曲线研究了合成物质对A3钢的缓蚀性能。失重实验表明BM是一种良好的缓蚀剂,25℃,在1mol·L^-1 HCl中,缓蚀剂浓度1mmol·L^-1时,对A3钢的缓蚀率达到96.7％,在0.5mol·L^-1 H2SO4体系中,当缓蚀剂用量为2mmol·L^-1时,缓蚀率为86％。通过模型拟合表明BM符合EL-Awady吸附。极化曲线表明其是一种阴极型缓蚀剂。