Modelling of Corrosion Inhibitor Efficiency of Carbon Steel in Seawater By Holographic Interferometry and Electrochemical Impedance Spectroscopy

Abstrak : Salah satu upaya pencegahan korosi pada logam dapat dilakukan dengan penambahan inhibitor ke dalam larutan uji. Inhibitor korosi yang dicoba adalah benzotriazol (BTAH) dan sistein (Cys). Penentuan laju korosi Cu-37Zn tanpa dan dengan adanya inhibitor korosi dilakukan secara elektrokimia dengan menggunakan teknik Electrochemical Impedance Spectroscopy (EIS). Hasil penelitian ini menunjukkan bahwa pada larutan uji dengan komposisi : 5,3 ppm Ca(NO3)2, 78 ppm NaCl dan ion sulfida sebesar 15 ppm diperoleh bahwa efisiensi benzotriazol (80 ppm) dan sistein (25 ppm) pada suhu kamar berturut-turut sebesar 40,74% dan 68,16%. Inhibitor yang di uji dalam penelitian ini teradsorpsi secara fisik pada permukaan logam Cu-37Zn dengan energi bebas adsorpsi (ΔGads) benzotriazol dan sistein berturut-turut adalah –18,53 dan –23,03 kJ/mol. Kata kunci : Inhibitor, EIS, Benzotriazol, Sistein Abstract : An effort to prevent of the corrosion can be performed by mean of inhibitor corrosion addition into the sample of water. We also investigated benzotriazole (BTAH) and cysteine (CYS) as inhibitor. The rates of corrosion Cu-37Zn in absence and presence of the corrosion inhibitor were determined by using Electrochemical Impedance Spectroscopy (EIS) technique. The obtained results were indicated that at sample of water with composition of 5.3 ppm Ca(NO3)2, 78 ppm NaCl and 15 ppm sulfide ion, the inhibitor efficiency of benzotriazole (80 ppm) and cysteine (25 ppm) at room temperature were 40.74% and 68.16% respectively. Since both inhibitors were physicaly adsorbed on Cu-37Zn with adsorption free energy (ΔGads)of benzotriazole and cysteine is –18.53 kJ/mol and –23.03 kJ/mol respectively. Keywords : Inhibitor, EIS, Benzotriazole, cysteine.

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The Protection of Reinforcing Steel in Concrete by Migrating Corrosion Inhibitor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.629-630.136 ◽

2014 ◽

Vol 629-630 ◽

pp. 136-143

Author(s):

J.S. Cai ◽

C.C. Chen ◽

J.Z. Liu ◽

L. Shi

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Carbon Steel ◽

Impedance Spectroscopy ◽

Corrosion Inhibitor ◽

Linear Polarization ◽

Polarization Resistance ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Reinforcing Steel ◽

Linear Polarization Resistance

In this paper, the performance of two kinds of migrating corrosion inhibitors on the corrosion behavior of steel in concrete under wet-dry cycle was investigated. The wet-dry cycle duration on the open circuit, current density and impedance of carbon steel imbedded in concrete were analyzed by linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS). The results show that two kinds of migrating corrosion inhibitors can restrain corrosion of reinforcing steel, the corrosion efficiency of ZX was less more than MCI. Migrating corrosion inhibitor not only can improve carbon steel impedance, also can improve concrete resistant. Key words: migrating corrosion inhibitor;Cl-;reinforcing steel;linear polarization resistance;electrochemical impedance spectroscopy

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Propolis Extract as Corrosion Inhibitor of Iron Alloy Immersed in an Ethylene Glycol / Water, 0.1 M NaCl Solution

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.406.265 ◽

2021 ◽

Vol 406 ◽

pp. 265-273

Author(s):

Hakima Hachelef ◽

Abdallah Khelifa ◽

Abderrahim Benmoussat

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Ethylene Glycol ◽

Corrosion Inhibitor ◽

Electrochemical Impedance ◽

Iron Alloy ◽

Activation Parameters ◽

Propolis Extract ◽

Solution Interface ◽

Isotherm Adsorption

The behaviour of a corrosion inhibitor based on proplolis extract via an iron alloy immersed in an electrolyte containing ethylene glycol water in NaCl 0.1 M was evaluated by a stationary technique not destructive which is the technique of electrochemical impedance. The diameter of the Nyquist curves increases with the increase of the concentration of propolis extract and it reaches an optimum concentration at 1.25 g / L, the maximum surface coverage percent at this concentration is 71.98% .The activation parameters reveal that the inhibitor molecules on iron surface are absorbed by physisorption and a chimisorption and obey Langmuir isotherm adsorption. These results were supplemented by Scanning electron microscopy (SEM) and (EDX) spectrum of chemical composition. The metal solution interface is simulated as a physical model by using electrochemical impedance spectroscopy (EIS). Keywords: Iron Alloy, Propolis extract, ethylene glycol;, Lamgmuir isotherm, Electrochemical impedance Spectroscopy (EIS).

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Inhibitive Effect by Acid Extract of Ficus Exasperata Leaves on the Sulphuric Acid Corrosion of Mild Steel

E-Journal of Chemistry ◽

10.1155/2009/413421 ◽

2009 ◽

Vol 6 (s1) ◽

pp. S189-S194 ◽

Cited By ~ 6

Author(s):

N. S. Patel ◽

S. Jauhari ◽

G. N. Mehta

Keyword(s):

Weight Loss ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Mild Steel ◽

Corrosion Inhibitor ◽

Electrochemical Impedance ◽

Electron Microscopic ◽

Scanning Electron Microscopic ◽

Microscopic Studies ◽

Scanning Electron

Extract ofFicus exasperataleaves was investigated as corrosion inhibitor of mild steel in 1 N H2SO4using conventional weight loss, electrochemical polarizations, electrochemical impedance spectroscopy and scanning electron microscopic studies. The weight loss results showed that the extract ofFicus exasperatais excellent corrosion inhibitor. Electrochemical polarizations data revealed the mixed mode of inhibition. The results of electrochemical impedance spectroscopy shows that the change in the impedance parameters, charge transfer resistance and double layer capacitance, with the change in concentration of the extract is due to the adsorption of active molecules leading to the formation of a protective layer on the surface of mild steel. Scanning electron microscopic studies provided the confirmatory evidence of improved surface condition, due to the adsorption, for the corrosion protection.

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Crevice Corrosion Behaviors of X52 Carbon Steel in Chloride Containing Solutions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.1432 ◽

2013 ◽

Vol 652-654 ◽

pp. 1432-1435

Author(s):

Qian Hu ◽

Jing Liu ◽

Jie Zhang ◽

Feng Huang ◽

Xing Peng Guo

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Carbon Steel ◽

Impedance Spectroscopy ◽

Crevice Corrosion ◽

Electrochemical Noise ◽

Electrochemical Impedance ◽

Corrosion Process ◽

Nacl Solution ◽

Concentration Difference ◽

Corrosion Behaviors

The crevice corrosion behaviors of X52 carbon steel in two typical Cl--containing solutions were investigated by electrochemical noise and electrochemical impedance spectroscopy. Results show that oxygen concentration difference leads to the coupled current in NaCl + NaHCO3 solution while HAc concentration difference causes the coupled current in NaCl solution saturated with CO2 in the presence of HAc. There exists an apparent incubation stage during the crevice corrosion process of X52 carbon steel in the former. However, no obvious incubation period of crevice corrosion can be observed in the latter. Micrography shows that the crevice corrosion occurs indeed and the corrosion inside the crevice is not uniform.

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Nano-TiO2 Phosphate Conversion Coatings – A Chemical Approach

Electrochemical Energy Technology ◽

10.1515/eetech-2018-0006 ◽

2018 ◽

Vol 4 (1) ◽

pp. 47-54 ◽

Cited By ~ 3

Author(s):

Nilesh S. Bagal ◽

Vaibhav S. Kathavate ◽

Pravin P. Deshpande

Keyword(s):

Corrosion Resistance ◽

Electrochemical Impedance Spectroscopy ◽

Carbon Steel ◽

Impedance Spectroscopy ◽

Zinc Phosphate ◽

Electrochemical Impedance ◽

Low Carbon Steel ◽

Low Carbon ◽

Phosphate Coatings ◽

Coating Weight

AbstractThe present study aims at deposition of zinc phosphate coatings on low carbon steel with incorporated nano- TiO2 particles by chemical phosphating method. The coated low carbon steel samples were assessed in corrosion studies using electrochemical impedance spectroscopy and potentiodynamic polarization techniques (Tafel) in 3.5% NaCl solution. Morphology and chemical composition of the coatings were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy in order to observe growth of coating. Significant variations in the coating weight, porosity and corrosion resistance were observed with the addition of nano- TiO2 in the phosphating bath. Corrosion rate of nano-TiO2 chemical phosphate coated samples was found to be 3.5 milli inches per year which was 3 times less than the normal phosphate-coated sample (8 mpy). Electrochemical impedance spectroscopy studies reveal reduction of porosity of nano-TiO2 phosphate coated samples. It was found that nano-TiO2 particles in the phosphating solution yielded uniform phosphate coatings of higher coating weight, fewer defects and enhanced corrosion resistance than the normal zinc phosphate coatings (developed using normal phosphating bath).

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