Aluminium In HCl Solution Research Articles

Exploring the efficacy of Congo Red dye as a corrosion inhibitor for aluminum in HCl solution: An interdisciplinary study with RSM modeling and theoretical simulations

This study investigates Congo Red Textile Dye (CRD) as a corrosion inhibitor for aluminum in a 1.0 mol/L hydrochloric acid solution. Utilizing a comprehensive suite of analytical techniques, including gravimetric analysis, scanning electron microscopy (SEM), ultraviolet–visible spectrophotometry (UV–Vis), Electrochemical Impedance Spectroscopy (EIS), and Potentiodynamic Polarization curves (PDP), we assessed CRD’s adsorption mechanism and its corrosion inhibition effectiveness. Significant corrosion mitigation was observed, with the efficiency of inhibition EI (%) increasing alongside CRD concentration, achieving a maximum efficiency of 87.5 %. This enhancement in EI (%) decreases with rising temperatures, assessed across a range from 298 to 323 K. Response surface methodology (RSM) and central composite design (CCD) were employed for accurate corrosion rates (Vcorr) and EI (%) prediction. Additionally, theoretical analysis was performed using global and local reactivity descriptors along with molecular dynamics (MD) simulations. Theoretical results confirmed the widespread presence of nucleophilic and electrophilic sites, along with a strong affinity for the Al surface, suggesting CRD’s potential for enhancing corrosion resistance. This study proposes a potential pathway for the valorization of Congo Red dye, utilizing concentrations within non-toxic thresholds, thereby aligning with environmental safety and industrial application considerations.

A comparison of the corrosion inhibition on 1060 aluminum in HCl solution between water and alcoholic extracts of Mikania micrantha

A detailed comparison of the corrosion inhibitory effect of water extract of Mikania micrantha (MME (H2O)) and 40% ethanol extract (MME (40% C2H5OH)) was conducted on 1060 aluminum in 1.0 M HCl by gravimetric, electrochemical and surface analysis techniques. The results show that two extracts have excellent inhibition performance, MME (H2O) (97.0%) surpasses MME (40% C2H5OH) (93.6%) in terms of maximum inhibition efficiency. MME (H2O) is a mixed-type inhibitor, whereas MME (40% C2H5OH) is mainly a cathodic inhibitor. Salicylic acid, isochlorogenic acid C, sucrose, succinic acid, valine and guanine in MME contribute on the inhibitive action.

Anticorrosive properties of Eucalyptus (Nilgiris) leaves extract on 2S grade aluminium in acid solutions

The study is on the application of Eucalyptus leaves extract (ELE) as anticorrosive properties for aluminium alloy in 0.5 M HCl by using potentiodynamic polarization (PDP), gravimetric weight loss, and Electrochemical impedance spectroscopic (EIS) methods. The corrosion inhibition characteristics of ELE on aluminium in HCl solution have been examined. This investigation showed the finest inhibition efficiencies of 95.0%, 92.0% and 89.3% that were obtained from weight loss, PDP and EIS at concentration of 0.5% ELE at 303 K respectively. As per Langmuir adsorption isotherm models, an extract of Eucalyptus leaves was adsorbed on the metal surface. The effect of the temperature on the corrosion behaviour with adding of the best concentration of ELE was studied in the temperature range 313–333 K. It was found that inhibition efficiency is independent of temperature. The negative Gibb's free energy and activation parameters of the ELE were recorded and the results indicated that the adsorption rates were spontaneous. The results obtained from PDP and EIS shows that the corrosion inhibition procedure is charge transfer controlled, and the ELE works as a mixed-type inhibitor. The findings of SEM (Scanning electron microscopy) and AFM (Atomic forcemicroscopy) studies support the adsorption inhibition mechanism. The results of all the experiments conduct are consistent. The functional groups of the ELE were identified using Fourier transform infrared (FTIR) spectroscopy.

CORROSION INHIBITION OF ALUMINIUM IN HYDROCHLORIC ACID USING PITHECELLOBIUM DULCE AS A GREEN INHIBITOR

Mass loss method, thermometric method and SEM analysis have been employed to study the corrosion inhibition efficiency of aluminium in HCl solutions using ethanolic extracts of Pithecellobium dulce. The results reveals that the ehanolic extracts of different parts (leaves, stem bark, seeds and fruit pulp) of plant under study are good corrosion inhibitor among which stem bark extract is more efficient against corrosion. It is concluded that the inhibition efficiency increases with increasing concentration of inhibitor. Inhibition efficiency was found maximum upto 94.23% and can safely be used as cost effective, non pollutant and non-toxic green corrosion inhibitor.

Corrosion inhibition of aluminium in HCl Solution by ethanol extract of Ruellia Tuberosa L

The ethanol extract of Ruellia tuberosa L leaves (ERT) was used for Corrosion inhibition of aluminum in 0.5 M HCl using the weight loss method at various temperatures and immersion time. Further, the potentiodynamic polarization studies, electrochemical impedance spectroscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopic, and scanning electron microscope analyses were carried out. The experimental result implies that the addition of inhibitor increases corrosion inhibition efficiency at various temperatures and it diminishes with increasing acid concentration. The ERT molecule’s adsorption on active sites of the aluminum surface was endothermic and is in physicochemical nature and it followed Langmuir adsorption isotherm. The obtained impedance results displayed a high convergence and the potentiodynamic polarization study exhibits mixed-type inhibition. The FT-IR, EDX spectroscopy, and scanning electron microscope studies have made it firmer than the inhibitor species are adsorbed on the Al surface.

Adsorption behavior and corrosion rate model of sodium carboxymethyl cellulose (Na-CMC) polymer on aluminium in HCl solution

Adsorption behaviour and corrosion rate of Sodium carboxymethyl cellulose on aluminium was studied. Different concentration levels of Sodium carboxymethyl cellulose (Na-CMC) solution were applied on several prepared and polished aluminium coupons for a corrosion experiment. These coupons were totally immersed in 100ml of 0.5M solution of Hydrochloric acid (HCl) in an open beaker placed in a water bath at varying temperatures for 2-8hrs respectively. At every specified temperature and time interval, the immersed coupon specimen was withdrawn from the test solution, washed, dried and reweighed. The weight loss being the difference in weight of the specimen before and after immersion in the water bath was recorded for every coupon sample. The effects of concentration, temperature and time on corrosion rate were studied and from the various plots, it was observed that increase in the concentration of the inhibitor decreases the corrosion rate. The study of the adsorption behaviour showed that Na-CMC was physically adsorbed on the aluminium coupons and obeyed Freundlich adsorption isotherm with an activation energy of 32K.83j/mol and heat of adsorption of -18.21Kj/mol . The study also established a relationship between the corrosion rate, CR; concentration, C; temperature, T; and time t, through a mathematical model: CR = 3.8-5*T1.1617 - 0.00052t0.6176 - 0.0013C0.8012, the proportion of variance explained (R2) = 0.8658 (86.58%), From the Results of the experiment and the model, Na-CMC was found to be an active corrosion inhibitor of Aluminium in acidic environment.
 Keywords: Adsorption, Aluminium, concentration, Corrosion Rate, Weight Loss

Improved Corrosion Resistance of Aluminum in 0.5 M HCl Solution using Plasma Electrolytic Oxidation

Abstract In this paper, the plasma electrolytic oxidation (PEO) was used to improve the corrosion resistance of aluminum in 0.5 M HCl solution. Influence of many factors such as the composition of electrolytes, time and inorganic additives on the performance of PEO process have been investigated. The surface morphology of PEO films was inspected using SEM, EDX and XRD analysis. The electrochemical impedance spectroscopy (EIS) and polarization measurements were carried out to evaluate the corrosion resistance of aluminum. The hardness and reduced modulus of aluminum surface at different PEO process time were determined by nanoindenter measurements. The results showed that the best conditions for formation high efficient oxide layer on the aluminum surface during PEO process were carried out in 0.001 M NaOH electrolyte containing 9 × 10−5 M Na2WO4 for 5 min. The PEO process is able to inhibit uniform and pitting corrosion of aluminum in HCl solution. The surface morphology analysis showed that PEO process produce a highly resistant protective oxide layer, mainly composed of orthorhombic crystalline phase of α-Al2O3. This oxide characterized by its greater hardness.

Cassava starch-sodium allylsulfonate-acryl amide graft copolymer as an effective inhibitor of aluminum corrosion in HCl solution

Abstract Cassava starch-sodium allylsulfonate-acryl amide graft copolymer (CS-SAS-AAGC) was prepared by in situ polymerization of sodium allylsulfonate (SAS) and acryl amide (AA) in the presence of cassava starch (CS). The inhibition performance was tested by immersing aluminum in HCl solution using weight loss and electrochemical methods. CS-SAS-AAGC showed an inhibition efficiency as high as 95% at low inhibitor concentration of 100 mg/L. The inhibitive performance is much higher than that of CS, SAS, AA, CS/AA, CS/SAS or CS/AA/SAS mixture. The adsorption of CS-SAS-AAGC on aluminum surface was found to obey Langmuir adsorption isotherm. CS-SAS-AAGC behaves as a mixing-type inhibitor, while mainly inhibiting the cathodic reaction. Electrochemical impedance spectroscopy (EIS) has two time constants with a large capacitive loop at high frequencies followed by also a large inductive one at low frequencies. The inhibition of aluminum surface by CS-SAS-AAGC is evidenced through scanning electron microscope (SEM) and contact angle images. The adsorption mechanism was theoretically analyzed by quantum chemical calculation and molecular dynamic (MD) simulation.

Synthesis of baicalin derivatives as eco-friendly green corrosion inhibitors for aluminum in hydrochloric acid solution

Three baicalin derivatives named methyl ester of baicalin (BM), ethyl ester of baicalin (BE), and n-propyl ester of baicalin (BP) were synthesized in the laboratory using the traditional Chinese medicinal herb Scutellaria baicalensis Georgi as raw material. The inhibition effect of the as-synthesized baicalin derivatives was investigated as eco-friendly green inhibitors on the corrosion of aluminum in 1.0M HCl solution by weight loss and various electrochemical techniques. Results show that the baicalin derivatives exhibit excellent performance as inhibitors for aluminum corrosion. The synthesized baicalin derivatives suppress both the anodic and cathodic process and the compounds behave as mixed-type corrosion inhibitors for aluminum in HCl solution. Also, results obtained indicate that compound BM is the best inhibitor and the effectiveness of these inhibitors decreases in the order of BM>BE>BP. The maximum inhibition efficiency obtained at 25°C using BM=0.9 g/l was ∼95%. The interpretation of the inhibition due to adsorption of the compounds on the aluminum surface is according to Langmuir adsorption isotherm. The free energy of adsorption for inhibition process was determined on the basis of Langmuir adsorption isotherm. Surface analyses were performed to establish the mechanism of corrosion inhibition of aluminum in acidic solution. The formation of the adsorbed baicalin-Al3+ complex on the metal surface led to slow down the corrosion rate of aluminum and improvement of the inhibition process.

A Theoretical Study on Chemically Elegant Proton Pump Inhibitors in Search of Novel Green Corrosion Inhibitors

Aluminum and its alloys exhibit remarkable corrosion resistance property due to its ability to form a tightly adhered, invisible protective oxide layer. Although this layer prevents or decelerates the corrosion of aluminum in HCl solution under certain conditions, they have to be used with inhibitors in very extreme circumstances of industrial applications. However, traditional inhibitors normally include environmentally hazardous substances, and therefore the development of novel green inhibitors becomes an important and vogue research subject. In this work, quantum chemical calculation approach was deployed and the density functional theory at B3LYP/6-311G++(d,p) basis set level calculations were performed on PPI drugs for the purpose of investigating the relation between their molecular structure and inhibition efficiency. Quantum chemical parameters such as the highest and lowest occupied molecular orbital energy, energy gap, dipole moment, electronegativity and hardness were calculated and a favorable correlation between the theoretical data and the experimental results was found.

An electrochemical investigation of azole derivative on aluminum in 0.25 M HCl solution using EN and EIS techniques

PurposeThis study attempts to investigate corrosion inhibition properties of 1H-benzimidazole (B) and 1H-benzotriazole (BTA) on aluminum in 0.25 M HCl solution at different concentrations.Design/methodology/approachTo this end, electrochemical techniques including electrochemical noise (EN), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used.FindingsResults showed a greater corrosion inhibition efficiency of BTA than B on aluminum in HCl solution. BTA showed greater tendency to adsorption on the metal surface than B because of the inclusion of three nitrogen atoms.Originality/valueThe novelty of this work is comparing EN data with EIS and potentiodynamic polarization parameters.

Corrosion of iron and aluminum in acidic and basic media: theoretical and experimental investigation

Purpose The purpose of this investigation is to study the corrosion behavior of iron and aluminum in HCl and NaOH media by means of theoretical and experimental approaches. Design/methodology/approach For theoretical investigations, the quantum chemical calculation was performed. In this regard, the adsorption of OH− and Cl− on iron and aluminum surfaces was investigated. Furthermore, the natural bond orbital for the direction and magnitude of charge transfer interactions were calculated. In addition, the electrochemical evaluations based on potentiodynamic experiments were carried out. Findings The quantum chemical calculation results showed that the charge transfer from OH− to the iron surface is more than that from Cl−, and also the charge transfer from Cl− is more than that from OH− to aluminum cluster. Furthermore, these anions donate more electrons to the iron cluster than to the aluminum cluster. The experimental data showed that the rate of corrosion of iron in 1.0M NaOH solution was less than in 1.0M HCl solution. The corrosion of aluminum in HCl solution was less than that in NaOH solution. The rate of corrosion of iron in both solutions was less than that of aluminum. Originality/value The findings of this paper indicate that calculations based on the natural bond orbital analysis of the charge transfer rates from OH− and Cl− to the iron or aluminum surfaces, and their comparison with experimental results, exhibited excellent agreement.

Effect of polyvinylpyrrolidone – polyethylene glycol blends on the corrosion inhibition of aluminium in HCl solution

Purpose– The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium in HCl solutions at 30-60°C and to study the mechanism of action.Design/methodology/approach– The inhibitive effect of the homopolymers and polymer blend was assessed using weight loss and hydrogen evolution methods at 30 and 60°C. The morphology of the corroding aluminium surface without and with the additives was visualized using atomic force microscopy. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.Findings– Results obtained show that inhibition efficiency (η%) increases with increase in concentration of the polymers but decreases with increase in temperature. The inhibition efficiency of the homopolymers and their blends decreased with rise in temperature. Inhibition efficiency was found to be synergistically enhanced on blending the two homopolymers with highest inhibition efficiency obtained for (PEG:PVP) blending ratio of 1:3. The phenomenon of physical adsorption is proposed from the trend of inhibition efficiency with temperature.Research limitations/implications– The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as potentiodynamic polarization and electrochemical impedance spectroscopy.Originality/value– Studies involving the use of polymer blends/mixtures as corrosion inhibitor for metals in corrosive environments are scarce. The results suggest that the mixture could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the use of polymer–polymer mixtures to control acid-induced corrosion of metal.

Experimental and theoretical study on corrosion inhibition of oxime compounds for aluminium in HCl solution

The inhibition effect of three oxime compounds of acetone oxime (AO), 2-butanone oxime (BO) and cyclohexanone oxime (CO) on the corrosion of aluminium in HCl solution was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), quantum chemical calculation and molecular dynamics (MD) simulation methods. The results show that all oxime compounds are good inhibitors, and inhibition efficiency follows the order: CO>BO>AO. The adsorption of each inhibitor on aluminium surface obeys Langmuir adsorption isotherm. All these oxime compounds act as cathodic inhibitors. The probable inhibitive mechanism is proposed from the viewpoint of adsorption theory.

The Use of Glutamic Acid as Corrosion Inhibitor for Aluminium in Hcl Solution

The adsorptive and inhibitive action of glutamic acid towards general and pitting corrosion of aluminium in HCl solution was investigated using weight loss, gasometric and thermometric methods. Glutamic acid was found to inhibit the corrosion of aluminium in HCl solution. The inhibition efficiency of glutamic acid decreased with increase in temperature, period of immersion and HCl concentration, but increased with increasing glutamic acid concentration. Adsorption characteristics of glutamic acid have also been studied and it was found that the process obeys physical adsorption. Thermodynamic parameters including; Ea, Qads, ∆Sads, ∆Hads and ∆Gads for the adsorption process signifies a spontaneous process. While Langmuir, Frumkin, Flory- Huggins and El-Awardy isotherm adsorption models can be used to explain the mechanism of glutamic acid adsorption onto aluminium surface in HCl solution.

Inhibition Effect of Bamboo Leaf Extract on the Corrosion of Aluminum in HCl Solution

A bamboo leaf inhibitor(designated PSLE) was extracted from Phyllostachys sulphurea(Corr.Riviere) leaves using a series of C2H5OH-water solutions(20%-80%(volume fraction)). The solutions were characterized by Fourier transform infrared(FTIR) spectroscopy and ultraviolet- visible(UV- Vis)spectrophotometry. The total flavonoid content of the PSLE was determined. The inhibition effect of PSLE toward the corrosion of aluminum in HCl solution was studied by weight loss, potentiodynamic polarization,electrochemical impedance spectroscopy(EIS), and scanning electron microscopy(SEM). Density functional theory(DFT) quantum chemical calculations including solvent effects were used to investigate the adsorption of light by the two major components vientin and isovientin. The results show that PSLE is a good inhibitor and the adsorption of PSLE on the aluminum surface obeys the Langmuir adsorption isotherm. The inhibition efficiency increases with PSLE concentration while it decreases with temperature and HCl concentration. A good correlation exists between the total flavonoid content and the inhibition performance. This implies that the flavonoids are the major contributor to inhibition activity. PSLE behaves as a cathodic inhibitor. The EIS spectra are characterized by one large capacitive loop at high frequencies followed by a large inductive loop at low frequency values. The impedance value increases with increasing inhibitor concentration. SEM results confirm that the corrosion of aluminum is retarded remarkably by PSLE. The quantum calculation results indicate that the adsorption center of either vientin or isovientin is mainly a flavonoid backbone structure(FBS).

Experimental and theoretical study on corrosion inhibition of o-phenanthroline for aluminum in HCl solution

The inhibition effect of o-phenanthroline on the corrosion of aluminum in HCl solution was investigated by weight loss, open circuit potential (OCP), potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The neural and protonated molecular structures of o-phenanthroline were studied by quantum chemical calculation. The results show that o-phenanthroline is a good inhibitor, and the adsorption obeys Langmuir isotherm. From polarization curves, o-phenanthroline acts as a cathodic inhibitor. EIS spectra exhibit a large capacitive loop at high frequencies followed by a large inductive one at low frequencies. The inhibition action is confirmed by SEM images.

Đánh giá khả năng ức chế ăn mòn thép và nhôm của một số dãy hợp chất azometin

The corrosion inhibition efficiencies of 39 Schiff’s bases of series from aniline, ethylendiamine, cyclohexylamine and 4,4-benzidine in the 1M and 2M HCl solutions on the steel (CT-3) and aluminium (D16) have been studied. It seems that the azomethine compounds with aldehyde moieties of 3-indolyl group (B8, C8 and H8) strongly inhibited the corrosion on aluminium but the corrosion inhibition effects on steel are relatively low. The azomethine compounds with aldehyde moieties of p-nitrophenyl group (B1, C1 and H1) inhibited highly the corrosion of both steel and aluminium in HCl solution. The bis-(4-nitrobenzylidene) diethylamine (B1) compound can be used as a good corrosion inhibitor for low carbon steel and aluminium in HCl acid solution.

Study on Corrosion Inhibition Efficiency of Stem Alkaloid Extract of Different Varieties of Holy Basil on Aluminium in HCl Solution

Corrosion inhibition efficiencies of holy basil on Al in HCl solution were studied by weight loss and thermometric methods in presence and in absence of stem extract of three different varieties of holy basil viz. ocimum basilicum (<TEX>$E_B$</TEX>), ocimum canum (<TEX>$E_C$</TEX>) and ocimum sanctum (<TEX>$E_S$</TEX>). Inhibition efficiency increases with the increasing concentration of stem extract and decreases with increases in acid strength. Results show that all varieties under study are good corrosion inhibitors, among which, <TEX>$E_B$</TEX> is most effective. Maximum inhibition efficiency was found 97.09% in 0.5N HCl solution with 0.6% stem extract. The Langmuir adsorption isotherm indicates that surface coverage also increases with increasing in the concentration of extract of stem in HCl solution.

Inhibition by Jasminum nudiflorum Lindl. leaves extract of the corrosion of aluminium in HCl solution

The inhibition effect of Jasminum nudiflorum Lindl. leaves extract (JNLLE) on the corrosion of aluminium in HCl solution was studied by weight loss, polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The results show that JNLLE is a good inhibitor in 1.0M HCl, and the adsorption of JNLLE obeys Langmuir adsorption isotherm. Effects of immersion time and acid concentration on inhibitive performance were discussed. Polarization curves reveal that JNLLE acts as the cathodic inhibitor. EIS exhibits a large capacitive loop at high frequencies followed by a large inductive one at low frequency values.