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Article
Publication date: 2 January 2018

Ayssar Nahle, Fadoua El-Hajjaji, Abdeslam Ghazoui, Nour-Eddine Benchat, Mustapha Taleb, Rafik Saddik, Abdelmalik Elaatiaoui, Mohammed Koudad and Belkheir Hammouti

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by…

Abstract

Purpose

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by gravimetric measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS).

Design/methodology/approach

Weight loss measurements, potentiodynamic tests and EIS were performed during this study.

Findings

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to be a very efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 85 per cent with inhibitor concentration 1.0 × 10-3 M at 303 K.

Practical implications

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to play an important role in the corrosion inhibition of mild steel in acidic solution.

Originality/value

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

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 June 2002

A. El Ouafi, B. Hammouti, H. Oudda, S. Kertit, R. Touzani and A. Ramdani

The inhibition of the corrosion of the mild steel in 1M HCl by new bipyrazolic compounds has been studied by weight loss, electrochemical polarisation and electrochemical…

Abstract

The inhibition of the corrosion of the mild steel in 1M HCl by new bipyrazolic compounds has been studied by weight loss, electrochemical polarisation and electrochemical impedance spectroscopy (EIS) measurements. Results obtained reveal that these compounds are very good inhibitors. The inhibition efficiency increases with the increase of inhibitor concentration and reached 94 at 10–3M for the bipyrazoles studied. Potentiodynamic polarisation studies clearly reveal that the presence of the bipyrazoles does not change the mechanism of the hydrogen evolution reaction and they act essentially as cathodic inhibitors. The effect of temperature on the corrosion behaviour of mild steel in 1M HCl without and with the bipyrazoles at 10–3M was studied in the temperature range from 298° to 343°K. EIS measurements show the increase of the transfer resistance with the inhibitor concentration.

Details

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

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Article
Publication date: 3 June 2021

Jan van Helden, Pawan Adhikari and Chamara Kuruppu

A review of papers on public sector accounting in emerging economies, as published in the Journal of Accounting in Emerging Economies' (JAEE) first decade.

Abstract

Purpose

A review of papers on public sector accounting in emerging economies, as published in the Journal of Accounting in Emerging Economies' (JAEE) first decade.

Design/methodology/approach

A reflection on the issues covered and achievements made in the reviewed papers in the context of extant knowledge in this domain.

Findings

A majority of the research in JAEE is dominated by accounting reforms inspired by New Public Management (NPM). Performance management, budgeting and accrual accounting are the main topics in the reviewed research. NPM claims, which can range from usability and use of a new accounting repertoire to desirable impacts on efficiency and service delivery, are often not fulfilled. Many papers attempt to explain failing accounting innovations by the local context in which they are embedded, including political instability, poor governance and a lack of capabilities.

Research limitations/implications

The paper reviews research in a niche journal, but the findings are related to wider public sector accounting literature.

Practical implications

Public sector practitioners, but also researchers, need to move away from a focus on public sector reforms due to contextual circumstances leading to built-in failures and concentrate instead on understanding how the accounting repertoire works in practice, including routes for improvements therein.

Originality/value

An original framework for analysing public sector accounting research in emerging economies is proposed, which, among others, distinguishes between various ambition levels for achieving NPM reforms.

Details

Journal of Accounting in Emerging Economies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2042-1168

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Article
Publication date: 1 August 2005

M. Bouklah, B. Hammouti, M. Benkaddour, A. Attayibat and S. Radi

To study the effect of inhibition of new bipyrazole derivatives on the corrosion of steel in HCl media at various temperatures.

Abstract

Purpose

To study the effect of inhibition of new bipyrazole derivatives on the corrosion of steel in HCl media at various temperatures.

Design/methodology/approach

In this study, novel corrosion inhibitors, namely bipyrazoles were synthesised and tested as corrosion inhibitors for steel in 1 M HCl. The degree of corrosion was measured using various techniques including weight loss measurements, potentiodynamic polarisation, linear polarisation resistance (Rp) and impedance spectroscopy (EIS).

Findings

It was found that 1,5,5′‐trimethyl‐1H,2′H‐3,3′‐bipyrazole (P1) gave the best inhibition effect. The inhibition efficiency increased with the concentration of P1 to attain 79 per cent at 10−3 M. Good agreement between the various methods explored was observed. Polarisation measurements also showed that P1 acted essentially as a cathodic inhibitor. The cathodic curves indicated that the reduction of proton at the steel surface was an activating mechanism. P1 adsorbed on the steel surface according to Frumkin adsorption model.

Research limitations/implications

The synthesis route offers the possibility of other pyrazolic compounds to be tested in the future.

Practical implications

The inhibitory efficiency of P1 increased with the increase of both the concentration and the temperature (in the 298‐353 K range). As such, P1 can be used in chemical cleaning and pickling processes.

Originality/value

The originality of this work is the synthesis of new inhibitors based on pyrazolic organic compounds.

Details

Pigment & Resin Technology, vol. 34 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 13 November 2007

M. Benabdellah, R. Souane, N. Cheriaa, R. Abidi, B. Hammouti and J. Vicens

To evaluate the effect of synthesised calixarenes as new inhibitors on the corrosion of steel in HCl media at various temperatures.

Abstract

Purpose

To evaluate the effect of synthesised calixarenes as new inhibitors on the corrosion of steel in HCl media at various temperatures.

Design/methodology/approach

Calixarenes have been synthesised and tested as corrosion inhibitors. Gravimetric technique and potentiodynamic polarisation and impedance spectroscopy methods were used.

Findings

Calixarenes exhibited a good inhibition. Their efficiency decreases slightly with temperature.

Research limitations/implications

It was found that the inhibition efficiency increases with the concentration of inhibitors to reach 92 per cent at 10−4M.

Practical implications

The efficiency of calixarene derivatives increases with the concentration and falls slowly with temperature to attain 84 per cent at 353 K range. Calixarenes can be used in chemical cleaning and pickling processes.

Originality/value

The originality of this work is to find an inhibitor to give protection close to 100 per cent.

Details

Pigment & Resin Technology, vol. 36 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 15 June 2021

Olanrewaju Moses Adesusi, Olayide Rasaq Adetunji, Tunji John Erinle, Iliyasu Kayode Okediran, Olumide Olufunso Akinpelu and Samuel Oluyemi Ipadeola

The purpose of this paper is to investigate the mechanisms of low alloyed medium-carbon steel (LAMCS) corrosion in 0.5 M H2SO4 inhibited by seeds oils of rubber (SOR)…

Abstract

Purpose

The purpose of this paper is to investigate the mechanisms of low alloyed medium-carbon steel (LAMCS) corrosion in 0.5 M H2SO4 inhibited by seeds oils of rubber (SOR), Neem (SON) and Jatropha (SOJ) containing varying degree of free fatty acid (FFA).

Design/methodology/approach

Specific gravity, acid values and FFA compositions of oils were determined. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are techniques used to investigate the corrosion inhibition mechanisms with evaluated Gibbs free energy of adsorption.

Findings

Corrosion inhibition efficiencies of oils reached values >99% as obtained from PDP and EIS. Protective oxide layer was formed on LAMCS consequent on containment of carbonyl and hydroxyl groups in the FFA of SOR, SON and SOJ, respectively. The SOR and SOJ are found to be mixed inhibitors, whereas SON behaved as anodic inhibitor. Mechanism of adsorption of SOR was synergistic between physisorption and chemisorption, while SON and SOJ exhibited physisorption. SEM micrographs images showed that uninhibited sample exhibited thicker mass of corrosion products. Formation of protective oxide layer was confirmed by XRD diffractograms.

Practical implications

This study has shown that the need for modification of vegetable seed oils containing FFA is unnecessary as the hydroxyl and carbonyl groups of the FFA contained in the respective oil were found to be the center of adsorption of the oils on the steel surface. Hence, cost and by-products associated with modification of oils used as corrosion inhibitors are eliminated.

Originality/value

SOR, which has the highest percentage FFA, was found to be the most influential on the corrosion inhibition mechanism of LAMCS, specifically within 0.01–0.02 g/mL concentration. FFA contained in the respective seed oil aided formation of protective oxide layer at interface between H2SO4 and LAMCS, relative to amount composed.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 1 May 2006

Maryam Ehteshamzadeh, Taghi Shahrabi and Mirghasem Hosseini

In this paper, the main aim is to study the synergistic effects of alkanethiols upon inhibition of Schiff bases, N,N′‐ethylen‐bis and N,N′‐ortho‐phenylen‐bis in 0.5 M…

Abstract

Purpose

In this paper, the main aim is to study the synergistic effects of alkanethiols upon inhibition of Schiff bases, N,N′‐ethylen‐bis and N,N′‐ortho‐phenylen‐bis in 0.5 M sulphuric acid solutions.

Design/methodology/approach

Measurements were carried out in a three‐electrode cell assembly connected to the corrosion measurement system using software for Tafel polarization. Impedance measurements were carried out at open circuit potential using an electrochemical interface and frequency response analyzer at frequencies from 100 kHz to 10 MHz.

Findings

Results obtained revealed that at high concentrations, each of the investigated Schiff bases and 1‐dodecanethiol (DT) were good inhibitors when added separately to the corrosive media. The decrease in corrosion rate was associated with an increase in their concentrations. It was found that the presence of DT together with Schiff bases in corrosive medium increased inhibition effect, especially at low concentrations. Synergistic effect is discussed from viewpoint of their co‐adsorption. The adsorption of combined inhibitors was found to follow Langmuir isotherm. Thermodynamic calculations revealed that adsorption of combined inhibitors had a physical nature.

Research limitations/implications

In order to improve further the performance of Schiff bases and identifying their synergistic effects with other additives it is suggested that some more researches on other Schiff bases with other alkanethiol molecules must be done.

Practical implications

The results of this paper can be used for acid cleaning of carbon steel in which suitable inhibitor systems with the highest efficiency is required.

Originality/value

This paper reveals that the presence of DT molecules in solution encourage the adsorption of Schiff bases by facilitating the electrostatic co‐adsorption of Schiff base molecules through a synergistic effect.

Details

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

Keywords

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Article
Publication date: 4 September 2017

Asmae Bouoidina, Mehdi Chaouch, Abdelfattah Abdellaoui, Amal Lahkimi, Belkheir Hammouti, Fadoua El-Hajjaji, Mustapha Taleb and Ayssar Nahle

The inhibition effect of Foeniculum vulgare seeds’ (FVS) extract on the corrosion of mild steel in acidic medium was studied using weight loss, electrochemical impedance…

Abstract

Purpose

The inhibition effect of Foeniculum vulgare seeds’ (FVS) extract on the corrosion of mild steel in acidic medium was studied using weight loss, electrochemical impedance spectroscopy and Tafel polarization, as well as the surface morphology of the mild steel.

Design/methodology/approach

Weight loss measurements, potentiodynamic tests, electrochemical impedance spectroscopy studies and gas chromatography/mass spectrometry and scanning electron microscopy analysis of FVS extract were performed.

Findings

FVS extract acts as a good inhibitor for the corrosion of mild steel in 1.0 M HCl. The inhibition efficiency increases with the increase in inhibitor concentration but decreases with the increase of temperature.

Practical implications

FVS extract was observed to play an important role in the corrosion inhibition of mild steel in acidic solution.

Originality/value

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

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 4 January 2013

Ayssar Nahlé, Maysoon Al‐Khayat, Ideisan Abu‐Abdoun and Ibrahim Abdel‐Rahman

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of P,P′‐Bis (triphenylphosphonio) methyl benzophenone dibromide (TPPMB…

Abstract

Purpose

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of P,P′‐Bis (triphenylphosphonio) methyl benzophenone dibromide (TPPMB) on the corrosion inhibition of mild steel in 1.0M HCl solution, which will serve researchers in the field of corrosion.

Design/methodology/approach

Weight loss measurements were carried out on mild steel specimens in 1.0M HCl and in 1.0M HCl containing various concentrations (2×10−8M and 2×10−5M) of the laboratory synthesized TPPMB at temperatures ranging from 303 to 343 K.

Findings

TPPMB was found to be a highly efficient inhibitor for mild steel in 1.0M HCl solution, reaching about 98% at the concentration of 2×10−5M 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.

Practical implications

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.

Originality/value

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.

Details

Anti-Corrosion Methods and Materials, vol. 60 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 7 September 2015

Shabnam Ashhari and Ali Asghar Sarabi

– This paper aims to investigate the corrosion inhibition effects of indole-3-carbaldehyde and 2-methylindole on mild steel in 1 M HCl solution.

Abstract

Purpose

This paper aims to investigate the corrosion inhibition effects of indole-3-carbaldehyde and 2-methylindole on mild steel in 1 M HCl solution.

Design/methodology/approach

Indole-3-carbaldehyde and 2-methylindole as corrosion inhibitors of mild steel in 1 M HCl solution were investigated by polarisation and electrochemical impedance spectroscopy (EIS). Adsorption isotherm and mechanism were calculated. Quantum chemical calculations were used to find out a correlation between electronic structure of inhibitors and inhibition efficiency. Changes in the properties of metal surface in HCl solution in the presence of inhibitors were studied by contact angle measurements.

Findings

Polarisation results revealed inhibitors could reduce cathodic and anodic reactions rates on metal surface. EIS analysis showed that inhibition efficiency of indoles increases by increasing the inhibitors’ concentration; maximum inhibition efficiency was 95 and 94 per cent in solutions containing 1 mM indole-3-carbaldehyde and 2-methylindole, respectively. Inhibitors’ adsorptions on metal surface were confirmed by analysing the exposed metals’ surface through contact angles measurements. The adsorption of inhibitors was found to follow Langmuir isotherm. Quantum chemical calculations showed that a more positively charged benzene ring in the structure of two indole-based inhibitors would lead to higher adsorption to metal.

Originality/value

This research was carried out to understand the effects of two different functional groups (-C=O, -CH3) with different induction effects on the indole structure and on inhibition efficiency of corrosion inhibitors with the purpose of using these components in industrial application as acid wash solutions to etch and remove rusts from metal surfaces.

Details

Pigment & Resin Technology, vol. 44 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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