R. Hariharaputhran, A. Subramanian, Alice Arul Antony, P. Manisankar, T. Vasudevan and S. Venkatakrishna Iyer
A few nitrones such as N‐benzilidene aniline‐N‐oxide, N‐(O‐hydroxy benzilidene) aniline‐N‐oxide (HN) and N‐(α‐naphthylidene) aniline‐N‐oxide (NN) have been synthesised and…
Abstract
A few nitrones such as N‐benzilidene aniline‐N‐oxide, N‐(O‐hydroxy benzilidene) aniline‐N‐oxide (HN) and N‐(α‐naphthylidene) aniline‐N‐oxide (NN) have been synthesised and investigated for evaluating their efficiency as inhibitors for the corrosion of mild steel in 1M HCl at different concentrations of nitrones ranging from 0.025‐1.0mM and at different temperatures ranging from 30‐70°C. Among these compounds NN gives the best performance even at higher temperatures. Potentiodynamic polarisation studies reveal the fact that all compounds behave as mixed type inhibitors. Hydrogen permeation studies reveal the fact that all the compounds bring down the permeation current. The absorption of these compounds on the mild steel surface from 1M HCl obeys Temkin’s absorption isotherm.
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V. Rajasekharan and P. Manisankar
The purpose of this study is to introduce mechanochemically prepared polyaniline anticorrosive additives. In primer coating technology, there is an increasing interest in the…
Abstract
Purpose
The purpose of this study is to introduce mechanochemically prepared polyaniline anticorrosive additives. In primer coating technology, there is an increasing interest in the development of efficient anticorrosive additives which replace the conventional inorganic anticorrosive pigments like heavy metal chromates and phosphates normally added to primer paints for the coating on metals. Conducting polymers are found to be better alternatives.
Design/methodology/approach
Polyaniline phosphate is synthesized through solid-state conditions without using any solvent. The synthesized polyaniline phosphate is added in the primer formulation instead of zinc phosphate. Primers with different quantity of zinc phosphate are also formulated and studied for comparison. The comparison between their abilities to control corrosion of carbon steel were done with application of open-circuit potential monitoring, polarization and electrochemical impedance spectroscopy methods in 3.5 per cent NaCl solution.
Findings
Corrosion studies indicate that polyaniline phosphate can improve corrosion protection properties by taking part the passivation processes. The performance of polyaniline phosphate is better than zinc phosphate.
Originality/value
I certify that the results are from our original research and this paper is neither considered for publication elsewhere nor published previously.
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R. Manickavasagam, K. Jeya Karthik, M. Paramasivam and S. Venkatakrishna Iyer
Poly(styrenesulphonic acid)‐doped polyaniline has been synthesised and the influence of this polymeric compound on the inhibition of corrosion of mild steel in 1M HCl has been…
Abstract
Poly(styrenesulphonic acid)‐doped polyaniline has been synthesised and the influence of this polymeric compound on the inhibition of corrosion of mild steel in 1M HCl has been investigated using weight loss measurements, galvanostatic polarisation studies, electropermeation studies and a.c. impedance measurements. The polymer acts predominantly as an anodic inhibitor. Hydrogen permeation studies and a.c. impedance measurements clearly indicate a very effective performance of the compound as a corrosion inhibitor. The adsorption of the compound on the mild steel surface obeys Temkin's adsorption isotherm.
Xiangbin Liu, Fandi Meng, Ruiping Liu, Junlin Kou, Zeyang Zhang, Jianrong Feng, Li Liu and Fuhui Wang
The marine environment presents a great challenge to the anticorrosion properties of organic coatings applied on equipment. Since the compactness of coatings is critical in marine…
Abstract
Purpose
The marine environment presents a great challenge to the anticorrosion properties of organic coatings applied on equipment. Since the compactness of coatings is critical in marine environments, a novel nepheline-epoxy resin (N-EP) composite was introduced into organic coatings to improve the interfacial compatibility between the pigments and the binder. The purpose of this study is to evaluate the effectiveness of the N-EP composite in enhancing the corrosion resistance of the coatings in marine conditions.
Design/methodology/approach
These composite particles were prepared via the mechanical ball milling method at thermofield-assisted, leading to chemical bonding between inorganic nepheline and epoxy resin, the agglomeration of particles was avoided by this method. Fourier transform infrared spectroscopy, transmission electron microscope, particle size distribution, sedimentation and thermogravimetric-differential thermal analysis were used to verify the feasibility of thermal field-assisted mechanochemistry for achieving a direct reaction between epoxy resin and nepheline powder, as well as to determine the optimal reaction conditions. Additionally, water absorption tests, Electrochemical impedance spectroscopy and scanning electron microscope were conducted to assess the anticorrosive properties of the modified nepheline coatings.
Findings
The results further indicated that N-EP improved the barrier performance and mechanical properties of the coating. For example, after modified, the tensile strength of coating had increased from 41.96 ± 0.05–63.14 ± 0.05 MPa. This can be attributed to the less defective N-EP/binder interface and the uniform dispersion of N-EP in the coating. The optimal preparation conditions (500 r/min of ball grinding speed and 6 h of ball grinding time) for the composites were also studied for a superior corrosion resistance of the coating.
Originality/value
Thermofield-assisted mechanochemistry enables direct reactions between epoxy resin and nepheline powder, enhancing the dispersion stability and interfacial compatibility of N-EP. This modification improves coating compactness, reduces porosity and enhances corrosion resistance by strengthening the labyrinth effect on water diffusion.
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S. Rajendran, S.P. Sridevi, N. Anthony, A. John Amalraj and M. Sundaravadivelu
To evaluate the inhibition efficiency (IE) of polyvinyl alcohol (PVA) in controlling the corrosion of carbon steel immersed in neutral aqueous solutions containing 60 ppm of Cl−…
Abstract
Purpose
To evaluate the inhibition efficiency (IE) of polyvinyl alcohol (PVA) in controlling the corrosion of carbon steel immersed in neutral aqueous solutions containing 60 ppm of Cl−, in the absence and presence of Zn2+. To investigate the influence of sodium sulphite (Na2SO3), sodium dodecyl sulphate (SDS), pH and duration of immersion on the IE of PVA‐Zn2+ system. To analyse the protective film formed on the metal surface.
Design/methodology/approach
The IE has been evaluated by weight loss method. The protective film was analysed by FTIR and fluorescence spectra.
Findings
A formulation consisting of 100 ppm of PVA and 75 ppm of Zn2+ offered 81 per cent IE to carbon steel immersed in a solution containing 60 ppm of Cl−. A synergistic effect on inhibition of a combination of PVA and Zn2+ was observed during the tests. The protective film consisted of the Fe2+‐PVA complex and Zn(OH)2. It was found to be UV‐fluorescent. When SDS was added to the PVA‐Zn2+ system, the mixture showed maximum IE at the critical micelle concentration (200 ppm) of SDS (an anionic surfactant). The oxygen‐scavenging effect of Na2SO3 increased as the concentration of Na2SO3 was increased. At lower concentrations of Na2SO3, the transport of the inhibitors played a more major role than did the removal of dissolved oxygen. As the pH value was increased, the IE of the PVA‐Zn2+ system decreased. As the duration of immersion was increased, the IE was observed to decrease.
Research limitations/implications
Electrochemical studies such as polarization and AC impedance spectra will enlighten more on the mechanistic aspects of corrosion inhibition.
Practical implications
If this study is carried out at high temperature under simulated conditions, the findings may find applications in cooling water systems.
Originality/value
The role of transport of inhibitors towards the metal surface from the bulk of the solution, formation of micelles by surfactants, removal of dissolved oxygen by oxygen scavenger, competition between formation of insoluble iron‐inhibitor complex on metal surface and formation of soluble iron chloride in influencing the inhibitive property has been investigated. The protective film was analysed by FTIR spectra and fluorescence spectra.
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Susai Rajendran, B.V. Apparao and N. Palaniswamy
The formulation consisting of 50ppm polyacrylamide (PAA), 300ppm phenyl phosphonic acid (PPA) and 50ppm Zn2+ has 95 per cent inhibition efficiency in controlling corrosion of mild…
Abstract
The formulation consisting of 50ppm polyacrylamide (PAA), 300ppm phenyl phosphonic acid (PPA) and 50ppm Zn2+ has 95 per cent inhibition efficiency in controlling corrosion of mild steel in a neutral aqueous environment, containing 60ppm Cl—, a situation commonly encountered in cooling water systems. A discussion of mechanistic aspects of corrosion inhibition is based on the results obtained from a potentiostatic polarization study, UV‐visible, FTIR and luminescence spectra. The protective film is found to be luminescent and to consist of Fe2+‐PAA complex, Fe2+‐PPA complex and Zn(OH)2.
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S.U. Rahman, M.T. Saeed and Sk.A. Ali
To demonstrate corrosion inhibition capabilities of new cyclic nitrones, containing hydrophobic substituents.
Abstract
Purpose
To demonstrate corrosion inhibition capabilities of new cyclic nitrones, containing hydrophobic substituents.
Design/methodology/approach
A number of new cyclic nitrones were synthesized. Corrosion inhibition efficiencies of these organic inhibitors were determined by gravimetric and electrochemical methods, using carbon steel as the substrate metal and 1 M HCl at 60°C as the corrosive environment. Concentration of inhibitor was varied between 50 and 400 ppm.
Findings
All compounds exhibited excellent corrosion efficiencies that ranged between 90.0 and 98.3 percent in 1 M HCl at 60°C. Tafel tests corroborated these results.
Research limitations/implications
The inhibitors were tested in acidic medium. It is unknown how these inhibitors will function in the presence of other ions that are typically present in natural corrosive environment.
Originality/value
All organic compounds presented in this work are new and this is the first time their corrosion inhibition characteristics have been evaluated.
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Mulayam Singh Gaur, Rajni Yadav, Mamta Kushwah and Anna Nikolaevna Berlina
This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity…
Abstract
Purpose
This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.
Design/methodology/approach
Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.
Findings
This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.
Originality/value
This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.
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Shivani Shivani, Manisankar Datta, Seema Sharma and Shveta Singh
The growing pressure on businesses to balance environmental sustainability with profit maximisation has led to the development of green entrepreneurial orientation (GEO), which…
Abstract
Purpose
The growing pressure on businesses to balance environmental sustainability with profit maximisation has led to the development of green entrepreneurial orientation (GEO), which proactively integrates green practices into core business operations. Grounded in the ecological modernisation theory, GEO acts as a green management practice which helps in achieving competitiveness through environmental innovation. However, despite the growing emphasis on GEO, there remains a gap in understanding how specific drivers influence the organisational structures and processes that lead to GEO. Therefore, the study addresses this gap by analysing the key drivers of GEO using an integrated approach.
Design/methodology/approach
In this study, total interpretive structural modelling (TISM) and cross-impact matrix multiplication applied to classification (MICMAC) were used to identify and interpret the interrelationship between key drivers of GEO. Here, TISM technique aided in constructing a contextual relationship-based structural model of drivers, whereas MICMAC assisted in categorising the drivers based on their driving and dependence power. A case evaluation was also carried out in the Indian textile industry to validate the TISM model.
Findings
The result indicates that institutional pressure, managerial environment concern, organisational resilience and big data analytical capabilities are the most influential drivers of GEO at organisational level, and other drivers act as secondary and linked variables in this process. The MICMAC analysis further supports the results of TISM. In addition, the overall TISM model is validated in the Indian textile sector.
Practical implications
The study findings will assist researchers and policymakers in adopting a systematic approach to prioritise GEO in pollution intensive industries. Moreover, it will help managers in leveraging GEO to achieve strategic advantages amid environmental challenges.
Originality/value
This study is amongst the first to employ an integrated qualitative approach to analyse drivers of GEO.