Search results

The beneficial effect of halide ions on the inhibition of corrosion of carbon steel in 20 per cent HCl solution in the presence of some nitrogen‐containing compounds, cetyl pyridinium chloride, cetyl pyridinium bromide, and hexamine was investigated using potentiodynamic polarisation measurements. Potentiodynamic polarisation studies revealed that all the tested compounds were of anodic‐type inhibitors. All of the compounds were able to reduce the corrosion of carbon steel and their performance was enhanced by the addition of iodide ions. The increase in surface coverage in the presence of the iodide ions indicated that iodide ions enhanced the absorption of inhibitor compounds on the metal surface. Auger electron spectroscopic analysis confirmed the joint absorption of the compounds with KI.

The purpose of the paper was to investigate the use of aqueous extract of date palm (Phoenix dactylifera) leaf as a green inhibitor for corrosion of carbon steel in 1M hydrochloric acid (HCl) solution.

Extracts from the date palm were used as the main component of an environmentally friendly corrosion inhibitor for use in HCl pickling processes. Inhibition behavior on carbon steel in HCl was investigated using weight loss measurements, linear and potentiodynamic polarization curves, electrochemical impedance spectroscopy and scanning electron microscopy.

The results show that the extract exhibited good inhibition performance in 1M HCl. The inhibition efficiency increased with increase in the concentration of the inhibitor but decreased with increase in temperature. Inhibition efficiency also was found to increase as immersion time increased. The inhibitive action was due to adsorption of the date palm leaf components on the steel, which was consistent with the Langmuir isotherm.

Date palm leaf extract (DPLE) is an effective inhibitor at room temperature and can be used to protect plain carbon steel from corrosion in HCl solution.

This study provides new information on the inhibiting characteristics of DPLE under specified conditions. The environmentally friendly inhibitor could find possible applications in metal surface anodizing and acid pickling processes.

This study aims to study electrochemically and by weight-loss experiments the effect of UAE Rhazya Stricta Decne extract on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (ranging from 2.0 to 0.002 g/L.) of the UAE Rhazya Stricta Decne extract at temperatures ranging from 303 to 343 K.

The aqueous Rhazya Stricta Decne leaves extract was found to be a highly efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 90 per cent at 2.0 g/L and 303 K, a concentration considered to be very moderate. Even with one-tenth of that concentration, 0.2 g/L, an inhibition of about 82 per cent was obtained at 303 K. The rate of corrosion of the mild steel in 1.0 M HCl is a function of the concentration of the Rhazya Stricta Decne extract. This rate increases as the concentration of the Rhazya Stricta Decne extract is increased. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where HCl solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

The purpose of this paper is to study the effect of silicon and phosphorus content in steel suitable for galvanizing on its corrosion and inhibitor adsorption processes in steels/cetyltrimethylammonium bromide combined and KI (mixture)/5.0 M hydrochloric acid systems has been studied in relation to the temperature using chemical (weight loss), Tafel polarization, electrochemical impedance spectroscopy (EIS), scanning electronic microscope (SEM) analysis and Optical 3D profilometry characterization. All the methods used are in reasonable agreement. The kinetic and thermodynamic parameters for each steels corrosion and inhibitor adsorption, respectively, were determined and discussed. Results show that the adsorption capacity for Steel Classes A and B are better than Steel Class C surfaces depending on their silicon and phosphorus content. Surface analyses via SEM and Optical 3D profilometry was used to investigate the morphology of the steels before and after immersion in 5.0 M HCl solution containing mixture. Surface analysis revealed improvement of corrosion resistance of Steels Classes A and B in the presence of mixture more than Classes C. It has been determined that the adsorbed protective film on the steels surface heterogeneity markedly depends on steels compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.

The effect of silicon and phosphorus content in Steels Classes A, B and C on its corrosion and inhibitor mixture adsorption processes in 5.0 M HCl solution has been studied by weight loss, potentiodynamic polarization, EIS and surface analysis.

The inhibition efficiency of mixture follows the order: (Steel Class A) > (Steel Class B) > Steel Class C) and depends on their compositions in the absence of mixture according on their silicon and phosphorus content, that is, the corrosion rate increases with increasing of the silicon and phosphorus content. A potentiodynamic polarization measurement indicates that the mixture acts as mixed-type inhibitor without changing the mechanism of corrosion process for the three classes of mild steels.

Corrosion rate mild steels in 5.0 M HCl depends on their compositions in the absence of mixture according to their silicon and phosphorus content, that is, the corrosion rate increases with increasing silicon and phosphorus content. The adsorbed protective film on the steels surface heterogeneity markedly depends on steels class’s compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of 4‐vinylbenzyl triphenyl phosphonium chloride on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Electrochemical and weight loss measurements were carried out on carbon steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (1.0 × 10⁻⁷ to 1.0 × 10⁻⁴ M) of the laboratory synthesized 4‐vinylbenzyl triphenyl phosphonium chloride at temperatures ranging from 303 to 343 K.

4‐vinylbenzyl triphenyl phosphonium chloride was found to be a highly efficient inhibitor for carbon steel in 1.0 M HCl solution, reaching about 99 per cent at the concentration of 1 × 10⁻⁴ M at room temperature and about 96 per cent at 303 K, a concentration and temperature considered to be very moderate. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where hydrochloric acid solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of phosphonium salt corrosion inhibitors which are highly efficient and can be employed in the area of corrosion prevention and control.

The purpose of this paper is to investigate the inhibition effect of hydralazine hydrochloride as a corrosion inhibitor for mild steel in 1M HCl. The inhibition effect was studied at different temperatures, ranging from 303 to 333°K.

The inhibition efficiency of hydralazine hydrochloride was analyzed using weight loss, Tafel polarization, electrochemical impedance spectroscopy and surface morphology methods. The effect of temperature on the corrosion behavior of mild steel in 1M HCl was studied and discussed using an adsorption isotherm and activation parameters.

Weight loss, polarization and impedance showed that the inhibition efficiency increases with an increase in the concentration of hydralazine hydrochloride for mild steel in 1M HCl. The inhibitive action may be attributed to the adsorption of the inhibitor molecule on the active sites of the metal surface by the Langmuir adsorption isotherm. Polarization curves indicated that hydralazine hydrochloride acts as a mixed-type inhibitor. Scanning electron microscopy was performed on inhibited and uninhibited mild steel samples to characterize the surface. Thermodynamic parameter indicated that the adsorption of hydralazine hydrochloride is a spontaneous process and the adsorption occurs chemically.

The inhibition effect of hydralazine hydrochloride for mild steel has been investigated at different temperatures, ranging from 303 to 333°K. Hydralazine hydrochloride was a good inhibitor at a higher temperature.

Introduction Amines have been known for a number of years as effective corrosion inhibitors. Their efficiency is attributed to the presence of the nitrogen atom acting as the active centre for the adsorption of organic molecules on the metal surface. Several aliphatic and aromatic amines have been reported to serve as effective corrosion inhibitors for iron and steel in acidic solutions. The nitrogen‐containing corrosion inhibitor exhibited a very good performance in hydrochloric acid, but very little effect in sulphuric acid. Hence a study of the mechanism by which the corrosion rate is reduced when these organic compounds are added to solutions is of interest. In this study the inhibition of corrosion of mild steel in HCl and H2SO4 has been studied using different electrochemical techniques. Results are reported and discussed.

The corrosion behaviour of copper in dilute HCl solution of pH 1.8‐2, in the absence and presence of different additives of Na₂S, was studied by open circuit potential measurement, scanning electron microscopy and polarisation techniques. A complete covering of the surface with the strongly chemisorbed HS⁻ is achieved at ≥10 ppm Na₂S concentration. The addition of different concentrations of ethylene diamine (EDA) to HCl of pH 1.8‐2 promoted the dissolution rate, due to an increase in autocatalytic dissolution at the Cu metal surface. However, the synergistic inhibition effect between EDA and Na₂S, resulting from the adsorption of HS⁻ on the Cu metal, facilitated the adsorption of EDA.

This paper aims to introduce a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

This paper introduced a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

The experimental results indicated that the influence of pre-corrosion status on corrosion rate and effectiveness of corrosion inhibitor are significant. The corrosion inhibitors in both injection stage inhibited the corrosion process by preventing the contact of corrosive medium and steel surface through formation of a protective film on the surface of N80 steel. The corrosion rate of polymer degradant can be reduced to 0.63 g/m 2 h through subsection injection with different inhibitor.

This result will increase the production of polymer injection plugging wells through expanding the application of acidic-oxidized polymer degradant.

The influence of some N‐containing organic compounds such as tetraethanol‐β‐octadecenyl succinylamide (TOSA), morphonil‐β‐hexenyl succinylamide (MHSA), ammonium naphthenyltri‐n‐butyl chloride (ANBC) and 1‐(2,4,6‐trimethylphenyl)‐3‐diethylaminopropanol‐2 (TMAP) as inhibitors for the corrosion of carbonized steel in mineral acid (HCl and H₂SO₄) solutions with different concentrations has been studied by using gravimetrical, electrochemical and polarization corrosion test methods. Observes that all compounds having surface active properties behave as inhibitors of a functional active cathodic type and have an inhibition effect at the first stage of corrosion in both acids, but more effectively in H₂SO₄. Shows that inhibition effect increases with increase of temperature in 0.5N H₂SO₄ solution and decreases with increase of temperature for the higher concentrations of acidic solutions. Shows that TOSA and TMAP compared with MHSA and ANBC enchance protection properties of adsorption layer.