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Article
Publication date: 1 August 2003

S.T. Keera

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…

384

Abstract

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.

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Anti-Corrosion Methods and Materials, vol. 50 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 6 January 2012

Hesham Tawfik M. Abdel‐Fatah

The purpose of this paper is to carry out laboratory studies of the inhibition effect of tyrosine (Tyr) on the corrosion of low chromium alloy steel (ASTM A213 grade T22) in 7 wt…

306

Abstract

Purpose

The purpose of this paper is to carry out laboratory studies of the inhibition effect of tyrosine (Tyr) on the corrosion of low chromium alloy steel (ASTM A213 grade T22) in 7 wt percent sulfamic acid solutions.

Design/methodology/approach

The corrosion inhibitive effect of Tyr was investigated using electrochemical impedance spectroscopy (EIS) and the new technique electrochemical frequency modulation (EFM).

Findings

It was found that the inhibition efficiency increased with increasing inhibitor concentration, while a decrease was detected with the rise of temperature and stirring speed. The corrosion inhibition is due to physical adsorption of Tyr on the steel surface. Adsorption of the inhibitor molecule, onto the steel surface follows the Temkin's adsorption isotherm.

Originality/value

The obtained results from both methods (EIS and EFM) at different experimental conditions were in high agreement and almost similar. This is an indication that the EFM technique can be used efficiently for monitoring the corrosion inhibition under the studied conditions.

Details

Anti-Corrosion Methods and Materials, vol. 59 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 10 October 2016

Subir Paul

The purpose of this paper is to predict the life of a corroding metallic structure in seawater so that uncertain and unpredictable failures of a structure, leading to accidents…

134

Abstract

Purpose

The purpose of this paper is to predict the life of a corroding metallic structure in seawater so that uncertain and unpredictable failures of a structure, leading to accidents, can be prevented.

Design/methodology/approach

Pitting has been known to show a large scatter in the measurable parameters such as corrosion rate, maximum pit depth, time to perforation and so on. Scatter results from the influence on pit development on metal surface heterogeneity and from variations in the corrosive environment over time. All these facts suggest that randomness is an inherent and unavoidable characteristic of pitting corrosion over time, so that stochastic models have been developed to formulate pit depth as a function of parameters influencing the process. Since chloride penetrates the passive film of the metal surface, Cl ion distribution into the metal has been mapped by finite element method (FEM).

Findings

The maximum pit depth which decides the onset of perforation or leakage has been modeled by the following equation: d=36.31(ΔE)0.68×(Δt)0.35. Cl ion distribution within a pit and outside has been modeled for better understanding of pit initiation which till today is not fully understood.

Practical implications

Perforation and leakage of a tank, container, or pipeline occur when the depth of pitting reaches the section thickness of the material of which the metallic structures are made. The pitting corrosion is localized and occurs at any spot or site where electrochemical conditions (ΔE Equation (9)) are prone to pitting. This leads to unpredictable failures of the structures which may look polished and undamaged under naked eyes. In most metallic structures, pitting may be present at some spots, but failures occur only when the depth predicted by the model Equation (9) reaches the section thickness of the material. Thus, determining pipe to soil potential gives a guide to go for maintenance before pit depth reaches the material thickness, and thereby unpredictable failure can be prevented. Second, the map generated by FEM showing Cl distribution throws much information and light on movement of Cl ions from passive layer into the pit, which leads to its growth. This helps scientists and researchers to understand the mechanism and gives much insights on finding new methods for protection of structures.

Social implications

The work will guide the engineers and researchers to prevent unpredictable failures of structures leading to accidents and human and property loss and prevent environment pollution from spilling of oil from tank and pipeline.

Originality/value

This is an original work based on several laboratory-generated simulated experimental data.

Details

Multidiscipline Modeling in Materials and Structures, vol. 12 no. 3
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 December 2005

H.S. Awad and S. Abdel Gawad

To investigate the capability of a series of nitrogen‐based heterocyclic organic compounds in inhibiting corrosion of iron in HCl and elucidate the dominant active form of the…

920

Abstract

Purpose

To investigate the capability of a series of nitrogen‐based heterocyclic organic compounds in inhibiting corrosion of iron in HCl and elucidate the dominant active form of the applied compounds during the adsorption process to explore the mechanism of their action.

Design/methodology/approach

The tested compounds were pyrimidine containing compounds, which were selected, based on molecular structure considerations. Gravimetric method has been applied with various electrochemical techniques (polarisation resistance, polarisation curves and electrochemical impedance spectroscopy) to investigate inhibition efficiency and mechanism.

Findings

The inhibiting action of the investigated pyrimidine containing compounds depends primarily on their concentration and molecular structure. These compounds act as mixed type inhibitors and function via adsorption on the surface, which follows Frumkin adsorption isotherm. The inhibition by the tested pyrimidine derivatives could be attributed to their chemisorption on the metal surface forming donor/acceptor type of bond between the inhibitor molecules and the vacant d orbitals of the surface iron atoms. Contribution from electrostatic adsorption, via interaction between the protonated form of the inhibitor and the charged metal surface, is also possible.

Research limitations/implications

The applied inhibitors were tested in the presence of chloride ions as a corrosive medium. Whether these inhibitors will function well in the presence of other ions that are typically present in natural corrosive environment is unknown.

Originality/value

This paper provides useful information regarding inhibition effect of pyrimidine and series of its derivatives. The outcome of this work contributes to better understanding of the mechanism of inhibition by this class of N‐based heterocyclic organic compounds.

Details

Anti-Corrosion Methods and Materials, vol. 52 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 27 September 2018

De Ding, Yue Zhang, Xiaobing Yu, Benling Fang, Jipu Guo, Jun Li, Lei Liu and Cuiwei Du

High-silicon cast iron has excellent corrosion resistance in some specific medium. But the effects of pH value, chloride concentration and soil moisture content on corrosion…

193

Abstract

Purpose

High-silicon cast iron has excellent corrosion resistance in some specific medium. But the effects of pH value, chloride concentration and soil moisture content on corrosion behavior are still unknown. This study aims to provide reference for the application of high-silicon cast iron in different environments.

Design/methodology/approach

Electrochemical impedance spectroscopy and potentiodynamic polarization curves were used to investigate the corrosion mechanism and rate. The morphology was observed by scanning electron microscopy. The chemical compositions of the corrosion products were detected by energy-dispersive spectroscopy and X-ray diffraction.

Findings

When the solution is acidic, the corrosion of high-silicon cast iron is more serious. When the chloride concentration is 0.1 per cent, the corrosion rate of high-silicon cast iron is the largest. A passive film is formed on the surface to prevent the corrosion reaction with the increasing of chloride concentration. The corrosion rate is the largest when water content is 15 per cent, and the corrosion is the lightest when water content is 30 per cent.

Originality/value

This study provides support for the selection of high-silicon cast iron as grounded material.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 26 September 2024

Yu Fu, Junwen Zhao, Xujia Li and Yiwen Peng

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle…

27

Abstract

Purpose

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle composites.

Design/methodology/approach

The morphology, composition and corrosion resistance of the coatings were analyzed by electrochemical tests, water contact angle tests, immersion tests, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction.

Findings

The composite coating with 0.3% MWCNTs and 0.5% nano-ZnO particles demonstrated both high shielding performance and cathodic protection performance, which was attributed to the porosity filling of MWCNTs and nano-ZnO particles together with the electrical connection of MWCNTs between the zinc and aluminum powders.

Originality/value

This work laid an experimental foundation for the preparation and corrosion mechanism of high corrosion-resistant chromium-free Zn–Al coating reinforced with MWCNTs and nano-ZnO particles.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 6
Type: Research Article
ISSN: 0003-5599

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Available. Content available
Article
Publication date: 1 December 2002

378

Abstract

Details

Disaster Prevention and Management: An International Journal, vol. 11 no. 5
Type: Research Article
ISSN: 0965-3562

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Article
Publication date: 5 December 2016

Rachel Povey, Lisa Cowap and Lucy Gratton

The purpose of this paper is to explore primary school children’s beliefs towards eating fruit and vegetables in a deprived area in England.

564

Abstract

Purpose

The purpose of this paper is to explore primary school children’s beliefs towards eating fruit and vegetables in a deprived area in England.

Design/methodology/approach

Semi-structured interviews were conducted with 11 children aged 9-11 from an after school club at a primary school in a deprived area in the West Midlands. Interviews were analysed using inductive thematic analysis.

Findings

Six master themes emerged from the data: “effect on the senses”, “feelings about food”, “healthy vs unhealthy foods”, “effects on health”, “convenience” and “family and friends”. Analysis showed that children seemed to have a very good awareness of the health benefits of eating fruit and vegetables. However, negative beliefs were associated with sensory perceptions (such as taste, texture, appearance and aroma), availability, and the competing desirability of other, unhealthy foods. Also, although parents were key influences, siblings and friends were often perceived as negative influences and would tease children about eating fruit and vegetables.

Practical implications

Suggestions for interventions include increasing the appeal and availability of pre-prepared fruits and vegetables in both home and school environments. Additionally, an approach to eating more fruit and vegetables which focusses on siblings and friends is advocated as these groups appear to play a key role in terms of promoting the consumption of these foods.

Originality/value

This study is novel as it uses individual interviews to explore primary school children’s attitudes towards fruit and vegetable consumption in a deprived area in England. By focussing on the specific behaviours of fruit and vegetable consumption, the findings aid the development of interventions that are designed to improve children’s healthy eating behaviour.

Details

British Food Journal, vol. 118 no. 12
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 1 October 1998

Z. Abdel Hamid, T.Y. Soror, H.A. El‐Dahan and A.M.A. Omar

The inhibiting effect of cationic surfactant N, N, N‐dimethyl 4‐methylbenzyl dodecyl ammonium chloride on mild steel in hydrochloric acid solutions was investigated by surface and…

670

Abstract

The inhibiting effect of cationic surfactant N, N, N‐dimethyl 4‐methylbenzyl dodecyl ammonium chloride on mild steel in hydrochloric acid solutions was investigated by surface and thermodynamic measurements, weight loss tests, polarization measurements and EDS techniques. The data obtained from surface and thermodynamic measurements with the inhibitor indicate that the area per molecule slightly increases with increasing temperature and both absorption and micellization processes are spontaneous. Weight loss measurement showed that the inhibition efficiencies increased with increasing surfactant concentration and attained a maximum around their critical micelle concentration. Polarization studies reveal that the inhibitor behaves as a mixed type in hydrochloric acid solutions and acted on the cathodic reaction without modifying the mechanism of the hydrogen evolution reaction. EDS measurement showed high coverage of surfactant on the mild steel surface.

Details

Anti-Corrosion Methods and Materials, vol. 45 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 December 1997

Z. Abdel‐Hamid

Four cationic corrosion inhibitors were prepared having the general formula ClRN+H2(CH2)nN+H2RCl, where R is a hydrogen atom or benzyl group, n = 8 or 10. Determines the critical…

423

Abstract

Four cationic corrosion inhibitors were prepared having the general formula ClRN+H2(CH2)nN+H2RCl, where R is a hydrogen atom or benzyl group, n = 8 or 10. Determines the critical micelle concentration (CMC) at 38, 48 and 58°C. Also investigates structural effects on the CMC, maximum surface excess (Γmax), and minimum area per molecule (Amin) at the aqueous solutions/air interface. Shows that these inhibitors provided a powerful corrosion inhibition of steel in sulphuric acid solution at temperatures up to 78°C. Also indicates that the alkylation process improved surface and thermodynamic properties, consequently attaining better inhibition effects.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 6
Type: Research Article
ISSN: 0003-5599

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