Insight into the Elemental Sulfur Corrosion of Carbon Steel in Chloride Bearing Media Using Electrochemical and Non-electrochemical Techniques

New method was used to prepare magnetite nanoparticle based on reduction of Fe(III) ions with potassium iodide to produce Fe3O4nanoparticle. The prepared magnetite was stabilized with cross-linked polymer based on 2-acrylamido-2-methylpropane sulfonic acid (AMPS to prepare novel core-shell nanogel. In this respect, Fe3O4/poly(2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) magnetic nanogels with controllable particle size produced via free aqueous polymerization at 65°C have been developed for the first time. The polymer was crosslinked in the presence of N,N-methylenebisacrylamide (MBA) as a crosslinker and potassium peroxydisulfate (KPS) as redox initiator system. The structure and morphology of the magnetic nanogel were characterized by Fourier transform infrared spectroscopy (FTIR) and transmission and scanning electron microscopy (TEM and SEM). The effectiveness of the synthesized compounds as corrosion inhibitors for carbon steel in 1 M HCl was investigated by various electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed enhancement in inhibition efficiencies with increasing the inhibitor concentrations. The results showed that the nanogel particles act as mixed inhibitors. EIS data revealed thatRctincreases with increasing inhibitor concentration.

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Green Approach to Corrosion Inhibition of Carbon Steel by Fucus spiralis extract in 1 M HCl Medium

Biointerface Research in Applied Chemistry ◽

10.33263/briac125.70757091 ◽

2021 ◽

Vol 12 (5) ◽

pp. 7075-7091

Keyword(s):

Carbon Steel ◽

Corrosion Inhibitor ◽

Surface Characterization ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Adsorption Model ◽

Corrosion Properties ◽

Uv Visible ◽

Fucus Spiralis ◽

Hcl Medium

The extract of Fucus spiralis (FS) was tested as a corrosion inhibitor of carbon steel in a 1M HCl medium. The anti-corrosion properties were analyzed by gravimetric and electrochemical techniques such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The surface characterization of carbon steel submerged in the optimal solution was carried out using UV-Visible, UV-Vis-NIR, and Optical microscopy analyses. Electrochemical and gravimetric results demonstrated that inhibitory efficiencies increase with increasing inhibitor concentration and the efficiency reaches 87% at a concentration of 0.5 g/L. According to Tafel extrapolated polarisation measurements, the FS also worked as a mixed-type corrosion inhibitor and changed the mechanism of anodic reactions. EIS analysis showed that a depressed capacitive loop dominates the Nyquist plot of impedance and enhances the polarization resistance (Rp) to 161.9 Ω cm2 with a reduction of the double layer capacity (Cdl) of carbon steel to 61.8 μF/cm2. This protection is assured by an adsorption mechanism based on the isothermal Langmuir adsorption model, which positively affects the thermodynamic parameters. UV-Visible, UV-Vis-NIR analyses exhibited that inhibitor decreases the iron oxides like hematite, Magnetite, and Goethite, Maghemite, Lepidocrocite, δ-FeOOH of the metal surface and delays the dissolution of the bare metal of iron to the ferrous ions, notably that optical morphology showed that FS extract decreases the aggressivity of HCl.

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Phenylcoumarin Glucoside as a Natural Inhibitor in the Protection of Low Carbon Steel Against Corrosion

MRS Advances ◽

10.1557/adv.2017.618 ◽

2017 ◽

Vol 2 (62) ◽

pp. 3909-3915

Author(s):

Héctor M. Barbosa Cásarez ◽

Araceli Espinoza Vázquez ◽

Francisco J. Rodríguez-Gomez

Keyword(s):

Carbon Steel ◽

Inhibition Efficiency ◽

Electrochemical Impedance ◽

Electrochemical Techniques ◽

Low Carbon Steel ◽

Steel Corrosion ◽

Low Carbon ◽

Low Concentrations ◽

Natural Inhibitor ◽

Polarization Studies

AbstractPhenylcoumarin glucoside (4-PC) is a compound extracted from the plant Hintona latiflora and was studied as inhibitor for AISI 1018 steel corrosion in 3% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques, which may find application as eco-friendly corrosion inhibitors. The 4-PC provides inhibitor properties that protect AISI 1018 low carbon steel against corrosion at low concentrations (5 ppm) obtained by EIS. Polarization studies showed that the inhibitor was of mixed type. The inhibition efficiency by the two electrochemical techniques shows similar results. The inhibitor adsorption was demonstrated to be a combined process (physisorption and chemisorption) according to the Langmuir isotherm.

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Corrosion in CO2 Systems with Impurities Creating Strong Acids

CORROSION ◽

10.5006/3110 ◽

2019 ◽

Vol 75 (11) ◽

pp. 1307-1314

Author(s):

Bjørn H. Morland ◽

Morten Tjelta ◽

Arne Dugstad ◽

Gaute Svenningsen

Keyword(s):

Sulfuric Acid ◽

Carbon Steel ◽

Stainless Steels ◽

Elemental Sulfur ◽

Experimental Studies ◽

Visual Observation ◽

Low Concentrations ◽

Strong Acids ◽

Safety And Environment

There are several proposed specifications for CO2 transport regarding how much impurities that can be allowed in the CO2 stream. Many of these specifications are based on health, safety, and environment (HSE) considerations in case of accidental spill, and only limited focus has been on the pipeline integrity. Previous work has demonstrated that many of the impurities that are expected to be present in CO2 captured from flue gasses may react and form corrosive species. The present paper studied impurity reactions and corrosion under simulated transport conditions (25°C and 10 MPa of CO2). An experiment was performed in a transparent autoclave which allowed for in situ visual observation. Chemical reactions between the impurities were observed even at very low concentrations (<100 ppmv). These reactions contributed to the production of nitric and sulfuric acid together with formation of elemental sulfur. Corrosion was observed on coupons of carbon steel, but not on stainless steels. The corrosion rate of carbon steel was low, but the amount of acids and solids (corrosion products) produced cannot be accepted from a pipeline integrity perspective. Further experimental studies are needed to determine specific limits for impurity concentrations in captured CO2 for transport.

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