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corrosion-inhibitor
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Modelling of the effect of operational parameters and concentration of some corrosion inhibitors on the corrosion of carbon steel
, Article Anti-Corrosion Methods and Materials ; Volume 49, Issue 6 , 2002 , Pages 426-432 ; 00035599 (ISSN) ; Kazemeini, M ; Safekordi, A ; Badakhshan, A ; Sharif University of Technology
2002
Abstract
Several corrosion inhibitors, such as, HEDP, sodium molybdate and zinc ions, were added to an aqueous corrosive media containing different concentrations chloride ions, and the corrosion rates (CRs) of carbon steel were measured at various temperatures. It was shown that, in the presence of more than 1,200 ppm of chloride ions, and temperatures greater than or equal to 42.5°C, the combination of HEDP, molybdate and zinc could not control the corrosion in a cooling water system. Then four different models were designed to represent the CR of carbon steel in presence of various corrosive parameters
Experimental and theoretical studies of media effects on copper Corrosion in acidic environments containing 2-amino-5-mercapto-1,3,4-thiadiazole
, Article Journal of the Iranian Chemical Society ; Volume 7, Issue 2 , June , 2010 , Pages 478-486 ; 1735207X (ISSN) ; Arshadi, M.R ; Biglar, M ; Sharif University of Technology
2010
Abstract
Corrosion behaviour of copper metal in acid solutions (HCl, H 2SO4 and H3PO4) containing 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) was investigated experimentally and theoretically via gravimetric, potentio-dynamic and quantum electrochemical approaches. Similar behavior was observed for H2SO4 and H3PO4 media, and related to the nature of anions at metal/solution interface. With regard to HCl, however, the rate of corrosion was determined to be low at initial stages, but high later on using an auto-catalyzing mechanism. In the presence of AMT, the experimental studies revealed that this molecule was a good anodic-type inhibitor causing substantial changes in corrosion potential. Moreover,...
Simulation of the effects of pozzolanic additives and corrosion inhibitor on the corrosion of reinforced concrete by artificial neural networks
, Article Revista Romana de Materiale/ Romanian Journal of Materials ; Volume 49, Issue 4 , 2019 , Pages 535-543 ; 15833186 (ISSN) ; Nobakhti, A ; Shokrgozar, A ; Afshar, A ; Sharif University of Technology
Fundatia Serban Solacolu
2019
Abstract
In this research, we simulate the corrosive behavior of steel reinforcements on 5 different mixtures to investigate the effect of two powerful protective methods, including pozzolanic additives and corrosion inhibitor on concrete, by artificial neural networks (ANNs). Related to this model, fly ash (FA), micro silica (MS), and slag were used as pozzolanic materials at an optimum 25%, 10%, and 25% of cement weight, respectively. Moreover, Ferrogard 901 as an inhibitor was also utilized. The producer recommends using12 kg/m3 to get the best possible results. The non-linear corrosion of concrete into a marine solution (3.5% NaCl) was simulated by the feed forward back propagation (FFBP)...
Simulation of the effects of pozzolanic additives and corrosion inhibitor on the corrosion of reinforced concrete by artificial neural networks
, Article Revista Romana de Materiale/ Romanian Journal of Materials ; Volume 49, Issue 4 , 2019 , Pages 535-543 ; 15833186 (ISSN) ; Nobakhti, A ; Shokrgozar, A ; Afshar, A ; Sharif University of Technology
Fundatia Serban Solacolu
2019
Abstract
In this research, we simulate the corrosive behavior of steel reinforcements on 5 different mixtures to investigate the effect of two powerful protective methods, including pozzolanic additives and corrosion inhibitor on concrete, by artificial neural networks (ANNs). Related to this model, fly ash (FA), micro silica (MS), and slag were used as pozzolanic materials at an optimum 25%, 10%, and 25% of cement weight, respectively. Moreover, Ferrogard 901 as an inhibitor was also utilized. The producer recommends using12 kg/m3 to get the best possible results. The non-linear corrosion of concrete into a marine solution (3.5% NaCl) was simulated by the feed forward back propagation (FFBP)...
Cluster approach to corrosion inhibition problems: Interaction studies
, Article Materials Chemistry and Physics ; Volume 86, Issue 2-3 , 2004 , Pages 311-314 ; 02540584 (ISSN) ; Lashgari, M ; Parsafar, Gh. A ; Sharif University of Technology
2004
Abstract
The interaction energies of 3,5 di-methyl pyridine (A) and 2,4 di-methyl pyridine (B) on the (100) surface of body-centered cubic (bcc) iron were determined via a cluster model and ab initio quantum chemical calculations at density functional theory level. The obtained energies were used to compare the inhibition behavior of these molecules for iron corrosion in hydrochloric acid solution. The iron surface and its adsorption sites (on-top, bridge, hollow) were considered as some clusters taken from two-layered 〈100〉 planes, i.e. Fe1(1), Fe4(2,2), and Fe5(4,1). So, the process for which quantum chemical calculations was carried out consists of adsorption of molecule A (B) on these clusters....
Evaluation of the Performance of Sheng (Tragopogon Buphthalmos Boiss) Extract as a Green Corrosion Inhibitor in High Concentration Hydrochloric Acid Solutions
, M.Sc. Thesis Sharif University of Technology ; Afshar, Abdollah (Supervisor)
Abstract
In this study, the extract of Tragopogon buphthalmos Boiss was investigated as a green or environmentally friendly corrosion inhibitor for mild carbon steels in high concentration hydrochloric acid solutions. Tragopogon buphthalmos Boiss was extracted using the extraction method of digestion at 50 ° C assisted by ultrasonic bath. Water-ethanol-acetone solvents were used in ratios of 30:35:35, respectively. The ratio of plant volume to solvent volume was one to ten. The container containing the extract was placed in a bath water at 50 ° C until the extract was in the form of gum, then stored at -15 ° C In a freezer. Infrared Fourier transform spectroscopy (FTIR) was used to determine the...
Effect of Oleuropein as Green Inhibitor on Corrosion Protection of Painted Steel
, M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad (Supervisor)
Abstract
The corrosion rate of steel (EN 10130 DC-04) in the presence of oleuropein in aqueous corrosive solutions (of different concentrations in 1M and 0.5M hydrochloric acid and also 3.5% sodium chloride) evaluated and results was shown that oleuropein can protect steel surfaces and it acts as good inhibitor. This means that the observations of linear polarization and weight loss experiments showed inhibitor efficiency more than 97% in acidic corrosive medium and above 74% for aqueous solution of 3.5% sodium chloride. Adding oleuropein at different concentrations (i.e. 300 ppm, 700 ppm, and 1000 ppm) to three different types of polymeric paint structures (nitrocellulose alkyd base, acrylic base,...
Evaluation of the Effect of Olive Leaf Extract (Olive Leaf) as a Green Inhibitor on Corrosion of Concrete Steel Reinforcements in the Persian Gulf Sea Water Simulator
, M.Sc. Thesis Sharif University of Technology ; Afshar, Abdollah (Supervisor)
Abstract
In this project, olive leaf extract has been investigated as a green corrosion inhibitor or in other words environmentally friendly for rebars embedded in concrete in the Persian Gulf Sea water simulator. Olive leaves were prepared by ultrasonic method at 50 ° C with the help of ethanol solvent. The water-ethanol solvent was 70:30 and the resulting extract was immediately applied to the concrete mix in specified doses. Portland cement type 2 according to ISIRI-389-96 standard has been used to prepare concrete. The resulting extract powder was added to the samples in four different doses: 2%, 4%, 6%, 8% by weight of cement to prove the inhibitory function as well as the cathodic or inhibitory...
Cluster/polarized continuum models for density functional theory investigations of benzimidazole corrosion inhibitors at metal/solution interface
, Article Corrosion ; Volume 62, Issue 3 , 2006 , Pages 199-206 ; 00109312 (ISSN) ; Arshadi, M. R ; Parsafar, Gh. A ; Sastri, U. S ; Sharif University of Technology
National Assoc. of Corrosion Engineers International
2006
Abstract
The molecular behavior of some benzimidazole (C7H 6N2) derivatives as corrosion inhibitors ojiron in hydrochloric acid (HCl) solution was investigated quantum electrochemically via the inhibitors' chemical potential (μ), molecular softness (σ), and the extent of charge transfer from the inhibitor to the metal (ΔN). These quantities were obtained from density functional theory (DFT) calculations for three models, i.e., isolated inhibitors (in vacua), inhibitors in solution, and, finally, inhibitors in electrical double layer (EDL). In these models, the effects of solvent, substrate, and electric field were considered using a polarized continuum model, iron Fe13(9,4) cluster, and a...
A simple and fast method for comparison of corrosion inhibition powers between pairs of pyridine derivative molecules
, Article Corrosion ; Volume 61, Issue 8 , 2005 , Pages 778-783 ; 00109312 (ISSN) ; Arshadi, M. R ; Parsafar, Gh. A ; Sharif University of Technology
National Assoc. of Corrosion Engineers International
2005
Abstract
Ab initio quantum chemical calculations at the density functional theory (DFT) level were performed on eight pyridine derivative molecules as corrosion inhibitors for iron in an acidic solution. In this regard, the geometry of the molecules were optimized using the B3LYP/6-31G method first, and then interactions of these optimized structures with the iron atom were explored using the B3LYP/LANL1MB method. Two modes of adsorption were considered, i.e., planar adsorption (P) via the pyridine ring and vertical adsorption (V) through a nitrogen atom. The interaction energy was minimized through the variation of the inhibitor molecule-iron atom distance. These minimum energy values, along with...
Fabrication of hollow carbon spheres doped with zinc cations to enhance corrosion protection of organosilane coatings
, Article Surfaces and Interfaces ; Volume 21 , 2020 ; Mahdavian, M ; Ramazani, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Hollow carbon spheres (HCS) are spherical forms of carbon materials that can be used as nanocontainers due to their empty cores. In this work, zinc cations were doped in HCS (Zn@HCS) from an aquatic solution of zinc nitrate salt. Corrosion inhibition of released zinc cations in saline solution on bare mild steel samples was assessed by EIS, polarization, and electrochemical noise measurements. The sample surfaces were characterized through FTIR spectroscopy and grazing incidence XRD analyses after exposure to the test solutions. The results showed improvement in the corrosion resistance in the presence of Zn@HCS in a long immersion period. Zn@HCS were also incorporated in organosilane...
A study of glycine-based dithiocarbamates as effective corrosion inhibitors for cold rolled carbon steel in HCl solutions
, Article Surfaces and Interfaces ; Volume 21 , 2020 ; Shockravi, A ; Mokarami Ghartavol, H ; Ziyaei Halimehjani, A ; Ostadrahimi, M ; Mirhosseini, S. M ; Behzadi, H ; Ghorbani, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The corrosion inhibition of glycine-based dithiocarbamates with benzyl (BDTC) and propyl (PDTC) groups were investigated for cold rolled carbon steel (CRS) in 0.5 M HCl, indicating that the compounds as mixed type inhibitors significantly reduced the corrosion rate of the CRS due to the formation of a stable protective film on the metal surface. As confirmed by ATR-FTIR, SEM, AFM, XPS and theoretical studies, chemically adsorbed BDTC molecule is a better corrosion inhibitor with higher corrosion efficiency of about 98% at room temperature and a better thermal stability attributed to the Fe-S and Fe-N bindings, and in addition, to the presence of the benzene ring in the molecular structure. ©...
DFT studies of pyridine corrosion inhibitors in electrical double layer: Solvent, substrate, and electric field effects
, Article Chemical Physics ; Volume 299, Issue 1 , 2004 , Pages 131-137 ; 03010104 (ISSN) ; Arshadi, M. R ; Sharif University of Technology
2004
Abstract
The molecular behavior of some pyridine derivatives as corrosion inhibitors of iron and aluminum in acid media, were studied quantum electrochemically. The calculations were made for three conditions; isolated inhibitor molecule, metal cluster, and finally polarized continuum media. It is concluded that for aluminum the vertical adsorption through nitrogen atom is prevailing, while for iron both vertical and planar adsorptions (through π electrons of aromatic ring) are possible, but the vertical is predominant. The inhibitor chemical potential (μ) and the extent of charge transfer (ΔN) to the metal were determined. A linear correlation between each of these and the inhibition efficiencies...
Inhibition effect of 3,5 bis (2-pyridil) 4-amino 1,2,4 triazole and 1-10 phenantrolin on corrosion of mild steel in acid solutions
, Article British Corrosion Journal ; Volume 37, Issue 1 , 2002 , Pages 76-80 ; 00070599 (ISSN) ; Hosseini, M. G ; Ghorbani, M ; Sharif University of Technology
IOM Communications Ltd
2002
Abstract
The inhibition effects of 3.5 bis (2-pyridil) 4-amino 1,2,4 triazole (NBTA) and 1-10 phenantrolin (PHEN), on corrosion of mild steel in acid solutions, (sulphuric acid and hydrochloric acid) were studied. The Tafel polarisation and ac impedance techniques were employed. Results obtained reveal that both compounds are relatively good inhibitors. The inhibition efficiencies of NBTA are higher in hydrochloric acid than in sulphuric acid. This has been attributed to the synergistic effect of chloride ions present in hydrochloric acid. The mechanism of inhibition of PHEN is believed to be owing to the formation of insoluble chelates between the organic molecules and atom/ion on the metal surface....
Probing the Performance of Safflower Plant as a Green Inhibitor with Molybdenum Disulfide on Corrosion Protection Properties of the Epoxy Coating
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadat Abadi, Ahmad (Supervisor) ; Mahdavian Ahadi, Mohammad (Supervisor)
Abstract
Today, the process of corrosion and compensation of minor injuries, without the need for tracing or any other physical interference, has become one of the subjects of interest to researchers. Inhibitors have been considered as one of the anti-corrosion agents. In this research, safflower extract as a green inhibitor in sodium chloride corrosive environment was used to evaluate the rate of corrosion of mild steel. Also the MoS2 nanoparticles were used as carrier of this green inhibitore in the epoxy coating to allow the activation of the coating in a scratched state in sodium chloride solution of 3.5%. In the first step, the extract of the safflower was prepared to reach the best part of this...
Fabrication and characterization of graphene-based carbon hollow spheres for encapsulation of organic corrosion inhibitors
, Article Chemical Engineering Journal ; Volume 352 , 2018 , Pages 909-922 ; 13858947 (ISSN) ; Ramazani, S. A. A ; Mahdavian, M ; Taheri, P ; Mol, J. M. C ; Sharif University of Technology
Elsevier B.V
2018
Abstract
In this work, we synthesized carbon hollow spheres (CHSs) using the silica templating method, encapsulated 2-mercaptobenzimidazole (MBI) inhibitor in the CHSs and evaluated their corrosion inhibition performance upon exposure of mild steel to a saline solution containing the released inhibitor. The effects of silica template surface modification on the CHS structure was evaluated, while the structure and morphology of the synthesized CHS was analyzed using field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), Raman spectroscopy and X-ray diffraction (XRD) spectroscopy. Furthermore, thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy...
A detailed atomic level computational and electrochemical exploration of the Juglans regia green fruit shell extract as a sustainable and highly efficient green corrosion inhibitor for mild steel in 3.5 wt% NaCl solution
, Article Journal of Molecular Liquids ; Volume 284 , 2019 , Pages 682-699 ; 01677322 (ISSN) ; Alibakhshi, E ; Bahlakeh, G ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Seawater, which has been frequently applied in cooling and injection water systems, imposes severe pitting corrosion to mild steel. Addition of green and sustainable inhibitors based on renewable sources is one of the promising methodologies for restricting metal corrosion in chloride-containing electrolytes. In this study, for the first time, from both theoretical and experimental faces, the role of Juglans regia green fruit shell (JRS) extract as a sustainable potent corrosion inhibitor for mild steel was studied. The chemical structure of the JRS extract was deliberated by Fourier transform infrared spectroscopy (FT-IR). By electrochemical techniques including polarization, EIS and...
Preparation and Characterization of Inhibitor Loaded Nanodiamond for Anticorrosion Coating
, M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar (Supervisor) ; Pirhadi, Nahid (Co-Supervisor)
Abstract
In recent years, nanodiamond (ND) has been used as reinforcement in polymeric nanocomposites in order to improve mechanical properties, thermal conductivity, etc. The surface of nanodiamond has several functional groups which make it appropriate adsorbent. In this study, nanodiamond was modified with dodecylamine corrosion inhibitor and was utilized (1wt %) in epoxy based nanocomposite. Fourier transform infrared spectroscopy (FTIR) analysis was used to confirm the surface modification of Nanodiamond. In order to estimate the loading amount of corrosion inhibitor, thermogravimetric analysis was investigated. FE-SEM analysis demonstrated nanoparticle dispersibility in epoxy matrix. Regarding...
The Effect of Inhibitors on the Corrosion of Automotive Aluminum in Water and Ethylene Glycol Environment
, M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad (Supervisor)
Abstract
In this study, the effects of different corrosion inhibitors on the corrosion of aluminum alloy which is used in the cooling systems of automotive industries were investigated. Also a comparison between the corrosion behaviour of the mentioned aluminum alloy with and without any galvanic connection to 5 different metals consist of solder, stainless steel, mild steel, brass and copper was done. The corrosion rate became more by establishing galvanic coupling. The base solution was ethylene glycol and water which is the base part of all antifreeze compounds. The tests were done at high temperature about 88ºC. Two different industrial corrosion inhibitors were examined in these conditions....
Experimental Investigation of Effects of Henna Extract as a Pre Flush Additive in Acidizing Operation
, M.Sc. Thesis Sharif University of Technology ; Masihi, Mohsen (Supervisor) ; Shadizadeh, Reza (Supervisor)
Abstract
Matrix acidizing treatment are performed to enhance the permeability of oil and gas formations by removing pore plug. Numerous additives have been introduced to aid the penetration of the acid or to perform other important tasks. To be able to pump the reactive fluid from the surface through the tubing and into the formation, corrosion inhibitors usually is necessary to protect the metal from attack by the fluid itself. In this work the Henna extract introduced as a pre flush additive and corrosion inhibitor in acidizing operation. It also enters the formation and effect on the matrix permeability and acidizing performance. The effect of Henna extract on permeability of rock will be...