Corrosion inhibitors for sweet (CO2 corrosion) and sour (H2S corrosion) oilfield environments

Summary Corrosion inhibitors are widely used to control corrosion under the sweet and sour environments in the oil and gas industry. More effective and environmentally friendly corrosion inhibitors need to be developed. This paper studies a new gemini imidazoline (GIM) corrosion inhibitor, in which two hydrocarbon chains and two head groups are linked by a rigid spacer. The GIM was synthesized through the reaction of oleic acid with triethylene tetramine at 2:1 molar ratio. The performance of the GIM on inhibition of carbon dioxide (CO2) corrosion was evaluated by linear polarization resistance in sparged-beaker testing. Rotating-wheel testing was performed to evaluate the film persistency of the test inhibitors. The results showed that corrosion inhibition of the GIM was more effective at lower concentration than that of conventional imidazoline. The mixture of GIM and fatty acid also showed better film persistency than conventional imidazoline. The emulsion tendency of the GIM was less than that of conventional imidazoline. The mechanism of the highly effective GIM was studied. It showed that GIM has much-higher surface activity than conventional imidazoline. The critical micelle concentration (CMC) of GIM is several times lower than that of conventional imidazoline. Hence, the new GIM corrosion inhibitor and its mixture give more-effective corrosion inhibition at low concentration; there is also a lesser environmental effect.

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The Salts of Nitronic acid as CO2-Corrosion Inhibitors

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v10i8.2254 ◽

2014 ◽

Vol 10 (8) ◽

pp. 3042-3052

Author(s):

Abbasov V. M. ◽

Aliyeva L. I. ◽

Haciyeva S. J. ◽

Mursalov N. I.

Keyword(s):

Protective Effect ◽

Corrosion Inhibitor ◽

Corrosion Inhibitors ◽

Isopropyl Alcohol ◽

Protective Layer ◽

Co2 Corrosion ◽

Isomeric Structure ◽

Branched Structure ◽

Higher Olefins ◽

Nitronic Acid

The salts of nitronic acids were obtained by nitration of higher olefins, both normal and isomeric structure in the presence of aqueous alkali. The resulting salts (Na+, K+, NH4+), were tested in CO2 -media as a corrosion inhibitor. The results showed that, the protective effect of the linear nitronated olefins increases by increasing the number of carbon atoms. This is due to the fact that because of the branched structure of the compounds, it is much more difficult to form a dense protective layer on the metal surface. 20% solutions of nitronated ethanolamine in isopropyl alcohol was synthesized and tested as corrosion inhibitor in carbon dioxide environments. The results showed that diethanolamine nitron based on a mixture of normal olefins C16-C18 at a concentration of 50 ppm has a high protective effect of 99.69%.

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The complexes of synthetic and petroleum acids N-derivatives as steel acidic corrosion inhibitors

Practice of Anticorrosive Protection ◽

10.31615/j.corros.prot.2020.96.2-2 ◽

2020 ◽

Vol 25 (2) ◽

pp. 18-25

Author(s):

L.I. Aliyeva ◽

L.M. Efendiyeva ◽

V.M. Abbasov ◽

G.Y. Rustamli ◽

S.F. Akhmedbekova

Keyword(s):

Carbon Dioxide ◽

Corrosion Inhibitors ◽

Atmospheric Oxygen ◽

Corrosion Process ◽

Molar Ratio ◽

Metal Loss ◽

Co2 Corrosion ◽

Carbon Dioxide Corrosion ◽

Catalytic Systems ◽

Heterogeneous Catalytic

Oxy- and petroleum acids were synthesized by liquid-phase oxidation of naphthen-paraffin concentrate, separated from diesel fraction of Azerbaijani oils mixture with atmospheric oxygen in the presence of heterogeneous catalytic systems. As the catalyst aluminum nano-oxide modified by Cr ,Co, Mn transition metals was used. The oxidation was carried out in reactor of bubble type in the interval of temperature 135…140 ºС during 5 h. Their imidazoline derivatives were obtained by the use of the synthesized acids and polyamines, and the complexes were prepared on the basis of them and aliphatic monobasic acids (formic and acetic) at equal molar ratio. Their influence was studied on the kinetics of the corrosion process of C1018 steel samples in 1% solution of NaCl, saturated by CO2 at 50 °С. The complexes were tested as inhibitors of carbon dioxide corrosion at concentration of 25 and 50 ppm in 20 h. According to obtained data, the usage of different concentrations of complexes decreases corrosion rate and metal loss (up to 9…10 times). The values of surface coverage (θ) and the extent of inhibition efficiency (IE, %) of corrosion process of steel example in CO2-medium in presence of prepared complexes were calculated. IR spectra of surface layer of used electrodes were recorded before and after adding prepared complexes into corrosion medium. As a result of the studies it was determined, that the obtained complexes had high prospects for use (protection degree 97…98%) as CO2-corrosion inhibitors in suppressing of carbon dioxide corrosion of steel equipment.

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Antagonistic effect and performance of CO2 corrosion inhibitors: Water chemistry and ionic response

Journal of Molecular Liquids ◽

10.1016/j.molliq.2019.111504 ◽

2019 ◽

Vol 293 ◽

pp. 111504 ◽

Cited By ~ 5

Author(s):

Mokhtar Che Ismail ◽

Solhan Yahya ◽

Pandian Bothi Raja

Keyword(s):

Water Chemistry ◽

Corrosion Inhibitors ◽

Antagonistic Effect ◽

Co2 Corrosion ◽

And Performance

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Corrosion of 16Mn in High Pressure Carbon Dioxide Saturated NACE Solutions with Hydrogen Sulfide

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.2615 ◽

2007 ◽

Vol 353-358 ◽

pp. 2615-2618

Author(s):

Qi Zhou ◽

Jian Jun Liu ◽

Qin Ma ◽

Gen Shun Ji ◽

Tie Ming Guo ◽

...

Keyword(s):

Pitting Corrosion ◽

Co2 Corrosion ◽

Experimental Conditions ◽

Hydrogen Damage ◽

H2s Corrosion ◽

Partial Pressure Of Co2 ◽

Weight Loss Method ◽

Loss Method ◽

Micro Analysis ◽

16Mn Steel

The paper deals mainly with the corrosion of 16Mn steel under the condition of three different high temperatures and in NACE solution saturated with H2S at 1MPa partial pressure of CO2, by means of autoclave, SEM, XRD, weight loss method and electron-probe micro-analysis. The result showed: under the experimental conditions, the serious CO2/H2S corrosion happened to 16Mn steel ,so that the main corrosion films, ferrous sulfide, could be clearly found on both sides of the samples; at 60°C, characteristics of pitting corrosion manifested centered chiefly around CO2 corrosion ; at 90°Cand 120°C, around H2S ones . It was the cooperating effects of both the hydrogen damage and pitting corrosion caused by CO2/H2S corrosion that formed the special corrosion features on the surface of steel to a certain degree. It was indicated that the corrosion of CO2/H2S was the result of interaction of multi-factors.

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