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Article
Publication date: 1 April 1984

Hugh McArthur

In tomorrow's world there will be more attention paid to the conservation of materials and energy. Energy is often a significant input in the production of materials. A…

Abstract

In tomorrow's world there will be more attention paid to the conservation of materials and energy. Energy is often a significant input in the production of materials. A greater realisation of the degradation mechanisms (and particularly corrosion) must be achieved in that corrosion is ‘an insidious consumer of our stocks of raw materials, a squanderer of our productive capacity and a dissipator of the fruits of our labours’. In real terms it costs about 4 per cent of the GNP of the UK, USA, or Japan and this is wasted ‘labour’. Another way of looking at these figures is to remember that a third of all the steel produced in the UK in one year goes to back to rust within the year.

Details

Structural Survey, vol. 2 no. 4
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 12 October 2018

Yanyan Pu, Zongchao Yu, Fengqin Wang, Yiyuan Fu, Tao Yan and Honglin Cheng

The purpose of this study is to develop luminescence sensors for the detection of nitroaromatic compounds (NACs) and metal ions to protect human health and prevent…

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Abstract

Purpose

The purpose of this study is to develop luminescence sensors for the detection of nitroaromatic compounds (NACs) and metal ions to protect human health and prevent environmental pollution.

Design/methodology/approach

The composition and morphology of Eu-metal-organic frameworks (MOF) (1) were well characterized by powder X-ray diffraction, elemental analyses, Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy and scanning electron microscopy. The emission spectrum displays that 1 has significant characteristic emission bands of Eu(III) ions. The authors further investigated the fluorescence sensing performances of 1 to NACs and metal ions.

Findings

The results show that Eu-MOF (1) exhibits significant fluorescence quenching effect toward p-nitroaniline and Fe3+ ions with good stability and recyclability. This means that 1 can be used as a multifunctional sensing material for the detection of p-nitroaniline and Fe3+ ions.

Originality/value

The authors have successfully synthesized a fluorescence Eu-based sensing material under hydrothermal conditions. In addition, the fluorescence property and sensing performances for detecting NACs and metal ions were studied. The results suggest that 1 has highly selective fluorescence quenching toward p-nitroaniline and Fe3+ ions with not only high sensitivity and selectivity but also excellent stability and recyclability. Furthermore, this study has confirmed that the multifunctional MOF material is very useful in environment pollutants’ detection and monitoring.

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Sensor Review, vol. 39 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 18 April 2019

J.H. Chen, P.S. Liu and W. Cheng

The purpose of this paper is to provide an investigation on a new kind of adsorbent materials, namely, the Prussian blue analog (PBA)-loaded albite-base porous ceramic…

Abstract

Purpose

The purpose of this paper is to provide an investigation on a new kind of adsorbent materials, namely, the Prussian blue analog (PBA)-loaded albite-base porous ceramic foam, which can effectively adsorb the heavy metal ion in the wastewater.

Design/methodology/approach

The natural zeolite powder has been used as the primary raw material to make a sort of porous ceramic foam by impregnating polymer foam in slurry and then sintering. Adjusting the technological parameters could control the bulk density of the ceramic product, which could float on water with the bulk density less than 1 g/cm3 and also sink in water with the bulk density higher than 1 g/cm3. After desilicating the porous ceramic foam, an Al-Fe type PBA with a strong function of ion exchange was loaded on the ceramic surface by directly yielding.

Findings

The adsorption performance for harmful metal ions was greatly improved by combining together the high adsorption capability of the PB analog and the efficient high specific surface area of the porous ceramic foam.

Originality/value

This work presents a PBA-loaded albite-base porous ceramic foam that can effectively adsorb the harmful substance in water, and the adsorption efficiency for some typical harmful ions, i.e., Cd2+, Cs+ and As(V), was examined under different conditions of the experimental period, the pH value and the ion concentration in the tested solution.

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Multidiscipline Modeling in Materials and Structures, vol. 15 no. 3
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 August 1997

G. Gunasekaran, R. Natarajan, V.S. Muralidharan, N. Palaniswamy and B.V. Appa Rao

Phosphonic acids are good complexing agents. However, they are not good as inhibitors except for a very few. Synergistic inhibition is offered in the presence of metal

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1110

Abstract

Phosphonic acids are good complexing agents. However, they are not good as inhibitors except for a very few. Synergistic inhibition is offered in the presence of metal cations like Ca2+, Mg2+, Zn2+ and others in neutral media. The zinc ion is an ideal choice. The part of zinc ions are now replaced by polymers, azoles to prepare eco‐friendly inhibitor formulations. They are also used as corrosion inhibitors in concrete, coatings, rubber blends, acid cleaners, anti‐freeze coolants, etc. Discusses the various applications of phosphonic acids and their action mechanisms.

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Anti-Corrosion Methods and Materials, vol. 44 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 June 2002

S. Rajendran, B.V. Apparao, N. Palaniswamy, A.J. Amalraj and M. Sundaravadivelu

Phosphonates have shown synergistic effects in combination with Zn2+ ions in controlling the corrosion of carbon steel immersed in neutral aqueous environments containing…

Abstract

Phosphonates have shown synergistic effects in combination with Zn2+ ions in controlling the corrosion of carbon steel immersed in neutral aqueous environments containing 60‐ppm Cl. The role of phosphonates in the presence of Zn2+ ions has been investigated by polarisation tests and weight loss results. It was observed that the phosphonates functioned as transporters of Zn2+ ions from the bulk of the solution towards the metal surface. The phosphonate‐Zn2+ bond is sufficiently strong to carry Zn2+ ions from the bulk solution towards the metal surface, but is weak enough for them to break to form a phosphonate‐Fe2+ bond at anodic sites on the metal surface. Inhibition efficiency increases when the phosphonate‐Zn2+ complex remains in solution in soluble form. Inhibition efficiency decreased when the phosphonate‐Zn2+ complex was precipitated in the bulk of the solution.

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Anti-Corrosion Methods and Materials, vol. 49 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 26 June 2018

Rahman Padash, Abdol Hamid Jafari and Effat Jamalizadeh

Study of corrosion behaviour could benefit from quantum chemical calculation to investigate the role of adsorption of main anions such as OH and Cl on metallic surfaces…

Abstract

Purpose

Study of corrosion behaviour could benefit from quantum chemical calculation to investigate the role of adsorption of main anions such as OH and Cl on metallic surfaces. The purpose of this study is to report the quantum chemical study of aluminium immersed in NaOH, NaCl and HCl solutions and verifying the calculations by potentiodynamic and open-circuit potential (OCP) measurements.

Design/methodology/approach

The electrochemical evaluations based on potentiodynamic polarization and OCP experiments were carried out. For theoretical investigations, the quantum chemical calculation was performed. In this regard, the adsorption of Cl, OH and H+ on aluminium surface was investigated. Furthermore, the natural bond orbital for the direction and magnitude of charge transfer interactions was calculated.

Findings

The calculations indicate that higher interaction energy between ions with the metallic cluster being modelled together with natural bond orbital calculations of direction and magnitude of charge transfer accurately predicts corrosion.

Originality/value

This paper shows that ions such as Cl, OH and H+ cause the corrosion of aluminium in NaOH, NaCl and HCl environments. The overall theoretical data corroborate with experimental results.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 May 2006

G. Lothongkum, P. Vongbandit and P. Nongluck

Aims to investigate the effect of chlorine on corrosion behaviours of stainless steels.

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1664

Abstract

Purpose

Aims to investigate the effect of chlorine on corrosion behaviours of stainless steels.

Design/methodology/approach

Very complicated thermodynamic calculations are needed to establish the E‐pH diagrams of commercial alloys, because they comprise of many elements. To avoid these complex calculations and facilitate corrosion prevention of AISI 316L stainless steel, the potentiodynamic method was used to construct the E‐pH diagram. The polarization curves were carefully experimented at the scan rate of 0.1 mV/s. The experimental conditions were aqueous solutions saturated with air (oxygen concentration 7.8‐8.5 ppm) containing chloride 0, 50, 500 and 5,000 ppm, pH 2, 4, 6, 8, 10 and 12, and at 25°C. The transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential were determined from the polarization curves and plotted with respect to the pH of the solution. The ions in solution were investigated by qualitative chemical analysis and stated in the E‐pH diagrams.

Findings

The constructed E‐pH diagrams showed clearly the effect of chloride concentration in the tested conditions on the transpassive or pitting potential, the protection potential of AISI 316L stainless steels. The ion states after pitting corrosion were different at low and high pH. This may be useful information for further investigation of pitting corrosion mechanisms.

Research limitations/implications

The E‐pH diagram was originally based on thermodynamic equilibrium. The potentiodynamic method was kinetically controlled and not in equilibrium. However, the experiments were kept at near stationary state as much as possible. The investigated E‐pH diagrams were limited for the solutions saturated with air containing chloride 0, 50, 500 and 5,000 ppm and at 25°C. The effects of temperature and other ions such as Fe3+, Mg2+, Ca2+, etc. on the transpassive or pitting potential, the protection potential, the primary passive potential and the corrosion potential should be further investigated, because natural water may contain those ions and is at high temperatures which could affect on the corrosion of AISI 316L stainless steels.

Practical implications

The investigated E‐pH diagrams may be applicable to avoid corrosion of AISI 316L stainless steels in similar conditions. The useful application may be for fields where natural water is not able to be treated, as is carried out in industry.

Originality/value

There have been several investigations on the effect of chloride on the corrosion behaviours of AISI 316L stainless steels. However, those investigations were carried out in different conditions. Very few experimental E‐pH diagrams of AISI 304L have been found, but not for AISI 316L stainless steels. The investigated diagrams showed also the ion states in pitting corrosion region which were influenced by pH. This may indicate the different pitting corrosion mechanism at different pH.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 September 1972

Galvanic corrosion It is commonly held that it is the electrochemical potential between two surfaces that is the controlling factor for the rate of corrosion. Table 1.2 in…

Abstract

Galvanic corrosion It is commonly held that it is the electrochemical potential between two surfaces that is the controlling factor for the rate of corrosion. Table 1.2 in chapter one of this series lists the standard oxidation potentials. However, the difference between the potentials of the two metals plus the difference in the e.m.f. due to the concentration of ions is the reversible electrochemical potential, which only applies when there is no current flowing. The degree of corrosion that occurs is based on the potential difference existing when there is a known current flowing. Thus the baser of two connected metals can be extremely corrosion‐resistant, even if the potential difference is quite large, provided at least one of them has good polarisation characteristics. Metals that are particularly damaging to ferrous metals not only have a very low potential, but are also to all practical purposes insoluble in the corrosive environment around the steel. Thus it is that one of the worst is copper.

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Anti-Corrosion Methods and Materials, vol. 19 no. 9
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 January 1968

I.R. Scholes

The general behaviour of titanium and zirconium in pure chemical environments is summarised, and also the effects of common contaminants such as air and heavy metal ions

Abstract

The general behaviour of titanium and zirconium in pure chemical environments is summarised, and also the effects of common contaminants such as air and heavy metal ions that are present in many process streams. The beneficial effect of traces of soluble iron and copper and organic compounds in non‐oxidising acids is discussed and the relative effect of these upon the behaviour of titanium and zirconium pointed out. Information is provided upon the performance of titanium—0.15% palladium alloy under similar circumstances. The conclusion suggests that the behaviour of titanium and zirconium in various types of chemical plant is best determined by reference to in‐plant trials than by laboratory testing; the use of in‐plant corrosion probes is recommended.

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Anti-Corrosion Methods and Materials, vol. 15 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 17 July 2018

A.G. Mohan Das Gandhi, K. Soorya Prakash and V. Kavimani

This paper aims to examine the investigations made on the corrosion behaviour of magnesium (Mg) substrate electrodeposited using different nano-materials.

Abstract

Purpose

This paper aims to examine the investigations made on the corrosion behaviour of magnesium (Mg) substrate electrodeposited using different nano-materials.

Design/methodology/approach

This study uses nano-materials such as those of reduced graphene oxide (r-GO), titanium-di-oxide (TiO2) and also r-GO/TiO2 nano-composites (dispersed through ultra-sonication process) at 3-min time interval. Crystalline nature of synthesized TiO2 is studied through X-ray diffraction and its pore volume is measured to be approximately 0.1851ccg-1 by Brunauer Emmett Teller analysis.

Findings

Surface morphology of the developed set of specimens inspected through scanning electron microscopy and energy dispersive spectroscopy establishes a clean surface coating and further witnesses for only minimal defects. Electrochemical behaviour of the developed coating is studied exhaustively using Tafel polarization and electrochemical impedance spectroscopy in 0.1 M Na2SO4 solution.

Originality/value

Incremental corrosion resistance exhibited by developed composite coating owes to the factors viz. chemical stability and hydrophobic tendency of TiO2 and r-GO; these known engineering facts resist the flow of ions into the corrosive media and thereby reduce the rate of corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

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