Corrosion of carbon steel under CO2 conditions: Effect of CaCO3 precipitation on the stability of the FeCO3 protective layer

Abstract IMPORTANCE OF THE SERUM SUBSTANCES The importance of the non-rubber components of latex, and particularly the protein components, in deciding the behavior towards coagulating agents was recognized at a relatively early date. Indeed, some investigators regarded the coagulating effect as being exerted only by way of the protein, the addition of the coagulants leading initially to its precipitation from solution in the serum, and thereby to the aggregation of the rubber globules. To-day the stability of latex as an aqueous dispersion of rubber globules is still regarded as being dependent on the non-rubber components of the latex. The material actually responsible for its stability, however, is now known to be adsorbed on the surface of the globules, and the physical behavior of the latex globules towards extraneous influences depends on the adsorbed film rather than on the rubber. This is remarkable, as the adsorbed layer, based on the approximation that one gram of protein covers a surface area of 107 cm.2, probably constitutes only 0.6% of the weight of the rubber globules, or thereabouts. The protective layer is not immovably attached, although in fresh latex it is possibly more firmly held than in preserved latex. It should be noted that the adsorbed coating normally represents only a small fraction of the total hydrophilic surface-active substances in the latex, and the stability of latex is less influenced by decrease in the proportion of the non-rubber components than might at first be expected. Latex purified by triply centrifuging shows little, if any, increased tendency to coagulation.

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Precipitation Behavior of Magnetite in Oxide Scale during Cooling of Microalloyed Low Carbon Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.572.249 ◽

2012 ◽

Vol 572 ◽

pp. 249-254 ◽

Cited By ~ 9

Author(s):

Xiang Long Yu ◽

Zheng Yi Jiang ◽

Dai Jun Yang ◽

Dong Bin Wei ◽

Quan Yang

Keyword(s):

Carbon Steel ◽

Oxide Scale ◽

Steel Substrate ◽

Low Carbon Steel ◽

Precipitation Process ◽

Low Carbon ◽

Precipitation Behavior ◽

Magnetite Particles ◽

And Migration ◽

The Stability

Precipitation behavior of magnetite particles in the thermal grown oxide scale during isothermal cooling of microalloyed low carbon steel was studied using scanning electron microscopy (SEM) and thin film X-ray. The oxide scale was generated from Gleeble 3500 Thermal Mechanical Simulator connected with a humid air generator, to simulate 550 and 450C isothermal treatments. Several types of magnetite precipitates were observed during different cooling processes with respect to the possible mechanisms of precipitation have been discussed. It is found that magnetite particles is as a result of pro-eutectoid precipitation from oxygen-rich wustite, and also as a product of the partial decomposition of wustite during the cooling process due to change of oxygen concentration and migration of iron ions. Furthermore, microalloyed elements in steel reduce the stability of wustite thereby facilitate the precipitation process, whose products of multi-phase oxide finally determine the adhesive strength of oxide scale and steel substrate.

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Role of Asphaltenes in Inhibiting Corrosion and Altering the Wettability of the Steel Surface

CORROSION ◽

10.5006/1.3651015 ◽

2011 ◽

Vol 67 (10) ◽

pp. 105006-105006-11 ◽

Cited By ~ 5

Author(s):

P. Ajmera ◽

W. Robbins ◽

S. Richter ◽

S. Nešić

Keyword(s):

Carbon Steel ◽

Steel Surface ◽

Protective Layer ◽

Contact Angles ◽

Co2 Corrosion ◽

Water Contact ◽

Internal Corrosion ◽

Corrosion Rates ◽

Mechanism Of Inhibition ◽

Carbon Dioxide Co2

Abstract Asphaltenes (heptane insolubles) from a variety of crude oils have been identified previously as contributors to inhibition of internal corrosion of mild steel pipelines. However, the mechanism of inhibition is unknown. To explore the mechanism, carbon dioxide (CO2) corrosion rates and wettability (oil/water contact angles) have been measured using Arab Heavy crude oil and its asphaltenes. Inhibition of CO2 corrosion rates for carbon steel was measured using electrochemical methods in a glass cell; wettability was assessed using contact angle measurements in a multiphase goniometer. The phase behavior of asphaltenes in corrosion and wetting was evaluated in the crude, toluene (C7H8), or heptol (70:30 mixture of heptane [C7H16] and toluene). Inhibition on steel exposed to a hydrocarbon phase increased with the concentration of asphaltenes in toluene. Inhibition by asphaltenes dissolved in toluene appears to be more effective than in the whole crude, at equivalent concentrations of asphaltenes. At 5 wt% in toluene, asphaltenes form a strong protective layer on the carbon steel surface, which reduces the corrosion rate and makes the surface hydrophobic. When the solubility of the oil is altered to the point where asphaltenes start to flocculate, it enhances the corrosion inhibition greatly. However, the inhibition is not as persistent as for the fully dissolved asphaltenes, and the surface needs to be periodically wetted with the oil phase to maintain the protection.

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A Green Pre-Film for Carbon Steel by Cerium Salt in Seawater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.72 ◽

2012 ◽

Vol 538-541 ◽

pp. 72-77

Author(s):

Li Li Gao ◽

Zheng Zhang ◽

Wei Zhen Wang ◽

Xiang Yu Hou ◽

Jing Wang ◽

...

Keyword(s):

Carbon Steel ◽

Protective Layer ◽

Processing Parameters ◽

Forming Process ◽

Effective Protection ◽

Environment Friendly ◽

Orthogonal Experiments ◽

Digital Microscope ◽

Cerium Salt ◽

Fe Hydroxide

An environment-friendly pre-film for carbon steel was obtained by using seawater with cerium salt. The influencing factors of cerium salt pre-film were discussed through orthogonal experiments, and the optimum processing parameters were confirmed. Then morphology, composition, the forming process and corrosion resistance of the pre-film were investigated. Analysis by digital microscope showed that the cerium salt pre-film was a blue uniform coating. EDS images displayed that the pre-film consisted of Ce, O and Fe, the major component of the protective layer was a mixture of Ce oxide, Ce hydroxide and Fe hydroxide. The results of electrochemical potentiodynamic polarization and gravimetric measurements indicated that the cerium salt pre-film provided effective protection to the substrate of carbon steel.

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Nephelium lappaceum Extract as an Organic Inhibitor to Control the Corrosion of Carbon Steel Weldment in the Acidic Environment

Sustainability ◽

10.3390/su132112135 ◽

2021 ◽

Vol 13 (21) ◽

pp. 12135

Author(s):

Femiana Gapsari ◽

Djarot B. Darmadi ◽

Putu H. Setyarini ◽

Hubby Izzuddin ◽

Kartika A. Madurani ◽

...

Keyword(s):

Carbon Steel ◽

Weld Metal ◽

Oxide Layer ◽

Base Metal ◽

Acidic Environment ◽

Protection Mechanism ◽

Steel Weldment ◽

Nephelium Lappaceum ◽

The Stability ◽

Organic Inhibitor

Organic inhibitors have been considered as an effective way to control the corrosion of carbon steel weldment in an acidic environment. This work proposes a new green organic inhibitor made of extract of rambutan fruit (Nephelium lappaceum) peel and aims at analyzing its corrosion inhibitor properties and protection mechanism. Specimens of carbon steel weldment were tested for their corrosion by using electrochemical and immersion methods in 1M HCl solution containing 0 to 6 g/L of Nephelium peel (NP) extract. Results showed that, in the same solution, the corrosion rate was measured to be higher on the weld metal zone than that of base metal zone, which could be related to the coarser grain of the weld metal zone and the stability of the formed oxide layer. The addition of NP extract was found to increase the stability of the oxide layer, thus increasing the corrosion resistance of the specimens. The maximum inhibition efficiency of the NP extract was reached at 97% for weld metal with 5 g/L of extract, at 80% for the heat affected zone with 5 g/L, and at 70% for base metal with 4 g/L. This work reveals the particularity of different weldment zones to the different needs of inhibitor concentration for obtaining the optimum corrosion protection.

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Inhibitory Properties of Neomycin Thin Film Formed on Carbon Steel in Sulfuric Acid Solution. Electrochemical and AFM Investigation

10.20944/preprints201709.0061.v1 ◽

2017 ◽

Author(s):

Adriana Samide ◽

Gabriela Eugenia Iacobescu ◽

Bogdan Tutunaru ◽

Roxana Grecu ◽

Cristian Tigae ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Sulfuric Acid ◽

Carbon Steel ◽

Acid Solution ◽

Sulfuric Acid Solution ◽

Steel Surface ◽

Protective Layer ◽

Force Microscopy ◽

Atomic Force ◽

Neomycin Sulfate

Our study aims to implement a strategy to reduce the carbon steel corrosion rate in sulfuric acid solution, using an expired drug with adsorption affinity on the metal surface. To investigate the corrosion protection efficiency of an environmental friendly inhibitor, namely neomycin sulfate (NMS), the electrochemical measurements were applied on carbon steel immersed in 1.0 M H2SO4 solution with and without NMS. The protective layer formed on the steel surface was studied by atomic force microscopy (AFM). The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) showed that the presence of the neomycin sulfate in acid solution leads to the decrease in corrosion current density (icorr) and the increase of polarization resistance (Rp). The mixed mechanism between physical and chemical adsorption of NMS molecules on the steel surface was proposed according to the Langmuir adsorption isotherm. The Atomic Force Microscopy (AFM) indicated that the NMS molecules contributed to a protective layer formation by their adsorption on the steel surface. The AFM parameters such as: root-mean-square roughness (Rq); average roughness (Ra) and maximum peak to valley height (Rp-v) revealed that in the presence of NMS a smoother surface of carbon steel was obtained, compared to the steel surface corroded in sulfuric acid blank solution.

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Passivation of Recirculating Open Water Cooling Systems Using New Organic Passivator

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/121028 ◽

2021 ◽

Vol 23 (12) ◽

pp. 375-386

Author(s):

Mahmoud Abbas ◽

◽

M. A. Shahin ◽

Mohamed M. I. Ahmed ◽

Magdy Kasem ◽

...

Keyword(s):

Carbon Steel ◽

Corrosion Rate ◽

Water System ◽

Cooling Water ◽

Protective Layer ◽

Steel Pipe ◽

Equilibrium Potential ◽

Nacl Solution ◽

Running Water ◽

Cooling Water System

It is well know that recirculating open cooling water system at metal/ water surface contact appear frequent corrosion products, like scales, foaling and material losses which are have great effect on cooling process. Passivation helps to maintain clean heat transfer surface by inhibiting oxides scales through creating outer passive layer. Passivators are substances which usually have a sufficiently high equilibrium potential and sufficiently low over potential decrease corrosion rate on attainment of passivity. One of the most popular passivator is organic phosphate Phosphinosuccinic oligomer C15H14O4P component (PSO) The study of passivation of carbon steel pipe line in recirculating open cooling water system was the aim of this present work. Maximum efficiency of passivator was determined and surface morphology were investigated using optical, scanning microscopy, phase analysis of the formed protective layer was exam by XRD and EDX. Corrosion in running water with and without PSO at 2 m3/hr flow rate was investigated using corrosion coupon rack. It was found that 200 ppm (PSO) decreases corrosion rate of carbon steel pipe in 3.5% NaCL solution from 23 to 7 mpy in stagnate water corrosion testing, while in running water in 3.5% NaCL solution it decreases from 45 to 18 mpy. XDR showed that the protective layer due to passivation is mainly Magnetite (Fe3O4) compound.

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Mechanism and inhibition efficiency of biomass Tetraselmis chuii sp. on carbon steel corrosion in the environment under the conditions of oil wells

Al-Kimia ◽

10.24252/al-kimia.v8i1.7230 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

Yayan - Sunarya ◽

Heli Siti H ◽

Munawaroh Munawaroh ◽

Gun Gun Gumilar

Keyword(s):

Carbon Steel ◽

Corrosion Inhibitors ◽

Inhibition Efficiency ◽

Protective Layer ◽

Steel Corrosion ◽

Marine Microorganisms ◽

Tetraselmis Chuii ◽

Mechanism Of Inhibition ◽

Biomass Extract ◽

Inhibition Ability

Corrosion control on petroleum pipe wells can only be done through the addition of corrosion inhibitors. In this study, the corrosion inhibitors studied were sourced from marine microorganisms, namely the type of microalgae Tetraselmis chuii sp. The aim to be achieved in this study was to determine the mechanism and efficiency of inhibition of the extraction of microalgae biomass in corrosion of carbon steel in an environment of petroleum conditions. To achieve this goal, a potentiodynamic polarization method (Tafel extrapolation) was used and the Electrochemistry Impedance Spectroscopy (EIS) method used the galvanostat-potentiostat device (Voltalab 40, PGZ 301). The results obtained from this study indicate that API 5L X65 carbon steel in the petroleum environment is very significantly corroded, caused by acidic media derived from acetic acid and dissolved CO2. The inhibition ability of the Tetraselmis chuii sp. Biomass extract. in line with the increasing extraction concentration reaching optimum at a concentration of 250 ppm with inhibition efficiency reaching 70%. The mechanism of inhibition takes place through the formation of a protective layer adsorbed on the surface of carbon steel. The protective membrane formed is uneven and tends to be porous.

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Adsorption Aspects, Inhibitory Properties and a Study of Surface Corrosion of Carbon Steel in Acidic Media

Modern Applied Science ◽

10.5539/mas.v10n10p82 ◽

2016 ◽

Vol 10 (10) ◽

pp. 82 ◽

Cited By ~ 4

Author(s):

Qhatan, A. Yousif ◽

Adel, A. Al-Zhara

Keyword(s):

Carbon Steel ◽

Protective Layer ◽

Steel Electrode ◽

Adsorption Models ◽

Isotherm Equation ◽

Surface Corrosion ◽

Langmuir Isotherm Equation ◽

The Impact ◽

Mixed Type Inhibitor

The impact of cupral compound on steel in presence of deaerated 0.25 M H2SO4 and 0.5M HClacidic solutions at 298.15K was examined by employing electrochemical measurements. It has been observed that the corrosion efficiency increased by increasing of cupral concentration of the corrosion inhibitor and this enhanced the inhibitory action as mixed type inhibitor. Several different adsorption models were examined which indicate the adsorption of cupral compound as inhibitor on the carbon steel electrode surface follows the Langmuir isotherm equation. The thermodynamic factors governing adsorption, as well as the parameters of kinetics corrosion have been estimated. The role of nanosilica has been observed to reduce the values of current density of corrosion process and this was confirmed by study the surface morphology of electrode via SEM-EDX and AFM techniques by formation a protective layer on carbon steel electrode.

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