CHAMBER PROTECTION OF ZINC BY INDIVIDUAL COMPOUNDS. ETHYLHEXANOIC ACID

Chamber protection is a promising and rapidly developing method of vapor-phase protection of metals from atmospheric corrosion by inhibitors. Corrosion screening of individual organic inhibitors has shown that chamber treatment (CT) with 2-ethylhexanoic acid (EHA) efficiently inhibits the initiation of zinc corrosion.
A set of accelerated corrosion, electrochemical and physical methods was used to study the specific features of zinc chamber protection and mechanisms of EHA action. It was shown that:
– as the temperature of zinc CT increases, the EHA efficiency first increases and then decreases. The growth of the protective effect is associated with an increase in the inhibitor’s vapor pressure that favors adsorption. The descending branch of the temperature dependence is due to a decrease in adsorption as the adsorbent (zinc) is heated. The optimal temperature of zinc CT with EHA is 100°C.
– the efficiency of EHA increases as the CT time is increased to 1 hour. This is the optimal duration for this system. Longer CT does not provide a positive effect and is inexpedient.
– CT of zinc under the optimal conditions results in the formation of surface adsorption films of EHA up to 100 nm thick. The acid reacts with the metal and the surface oxide to form the C4H9-CH(C2H5)-COO-Zn-OH basic salt. Once zinc is removed from the chamber and exposed to open air, the basic salt is dehydrated and converted to a compound with the formula CH(C2H5)-COO-Zn-O-Zn-OOC-СН(C2H5)-C4H9 that is responsible for metal protection. This process determines the growth in the protection efficiency during the first day of metal exposure outside the chamber at room temperature.
– the surface layers formed on zinc during CT followed by exposure to air passivate the metal and stabilize its passive state. Their action is associated with both shielding of the surface from the corrosive environment and inhibition of corrosion processes on the active metal surface. The EHA efficiency in zinc protection was confirmed by field tests.

1. A.M. El-Sherik, Trends in Oil and Gas Corrosion. A.M. El-Sherik. Research and Technologies, Woodhead Publishing, 2017, 12. ISBN: 9780081012192

2. Ю.И. Кузнецов и A.A. Михайлов Экономический ущерб и средства борьбы с атмосферной коррозией. Коррозия: материалы, защита. 2003, № 1, 3−10

3. D.M. Bastidas, E. Cano and E.M. Mora,Volatile corrosion inhibitors: a review. ANTICORROS METHOD M, 2005, 52, 71–77. doi: 10.1108/00035590510584771

4. S. Gangopadhyay and P.A. Mahanwar Recent developments in the volatile corrosion inhibitor (VCI) coatings for metal: a review, J. Coat. Technol. Res., 2018, 15, 789–807. doi: 10.1007/s11998-017-0015-6

5. F.A. Ansari, C. Verma, Y.S. Siddiqui, E.E. Ebenso and M.A. Quraishi, Volatile corrosion inhibitors for ferrous and non-ferrous metals and alloys: A review. Int. J. Corros. Scale Inhib., 2018, V.7, 2, 126–150. doi: 10.17675/2305-6894-2018-7-2-2

6. B. Valdez, M. Schorr, N. Cheng, E. Beltran and R. Salinas, Technological applications of volatile corrosion inhibitors, Corros. Rev., 2018, 36, 227–238. doi: 10.1515/corrrev-2017-0102

7. И.Л. Розенфельд и В.П. Персианцева, Ингибиторы атмосферной коррозии, М.: Наука, 1985, 278 c.

8. C. Fiaud, Theory and practice of vapour phase inhibitors, The Institute of Materials, London, 1994, 1-11 p.

9. N.N. Andreev and Y.I. Kuznetsov, Physicochemical aspects of the action of volatile metal corrosion inhibitors, Russian chemical reviews, 2005, 74, 8, 685. doi: 10.1070/RC2005v074n08ABEH001162

10. D.D.N. Singh and M.K. Banerjee, Vapour phase corrosion inhibitors–a review, Anti-Corrosion Methods and Materials, 1984, 31, 6, 4–22.

11. O.A. Goncharova, A.Yu. Luchkin, I.A. Archipushkin, N.N. Andreev, Yu.I. Kuznetsov and S.S. Vesely, Vapor-phase protection of steel by inhibitors based on salts of higher carboxylic acids., Int. J. Corros. Scale Inhib., 2019, 3, 586–599. doi: 10.17675/2305-6894-2019-8-3-9

12. A.Yu. Luchkin, O.A. Goncharova, I.A. Arkhipushkin, N.N. Andreev and Yu.I Kuznetsov, The effect of oxide and adsorption layers formed in 5- chlorobenzotriazole vapors on the corrosion resistance of copper, Journal of the Taiwan Institute of Chemical Engineers., 2020, 117, 231–241. doi: 10.1016/j.jtice.2020.12.005

13. O.A. Goncharova, A.Yu. Luchkin, N.P. Andreeva, V.E. Kasatkin, S.S. Vesely, N.N. Andreev and Yu.I. Kuznetsov, Mutual effect of components of protective films applied on copper and brass from octadecylamine and 1,2,3-benzotriazole vapors. Materials, 2022, 15, 1541. doi: 10.3390/ma15041541

14. A.Yu. Luchkin, O.A. Goncharova, Yu.B. Makarychev, I.A. Arkhipushkin, V.A. Luchkina, O.V. Dementyeva, I.N. Senchikhin and N.N. Andreev, Structuring of surface films formed on magnesium in hot chlorobenzotriazole vapors, Materials, 2022, 15, 6625. doi: 10.3390/ma15196625

15. O.A. Goncharova, D.S. Kuznetsov, N.N. Andreev, Y.I. Kuznetsov and N.P. Andreeva, Chamber Inhibitors of Corrosion of AMg6 Aluminum Alloy. Protection of Metals and Physical Chemistry of Surfaces, 2020, 56, 1293–1298. doi: 10.1134/S2070205120070060

16. ГОСТ 3640-94. Цинк. Технические условия. Москва, Стандартинформ. 2011, 38 с.

17. F. Mansfeld, M.W. Kendig and S. Tsai, Evaluation of Corrosion Behavior of Coated Metals with AC Impedance Measurements, Corrosion, 1982, 38, 9. 478–485. doi: 10.5006/1.3577363

18. F. Mansfeld, M.W. Kending and S. Tsai, Recording and Analysis of AC Impedance Data for Corrosion Studies, Corrosion, 1982, 37, 301–307. doi: 10.5006/1.3621688

19. F. Mansfeld, Use of electrochemical impedance spectroscopy for the study of corrosion protection by polymer coatings, J. Appl. Electrochem., 1995, 25, 187–202. doi: 10.1007/BF00262955

20. S.S. Vinogradova, I.O. Iskhakova, R.A. Kaidrikov and B.L. Zhuravlev, Impedance Spectroscopy Method in Corrosion Studies; KNITU Publishing House: Kazan: Russia, 2012, 96. (In Russian).

21. N. Mahato and M.M. Singh, Investigation of passive film properties and pittinp resistance of ALSI 316 in aqueous ethanoic acid containing chloride ions using elextrochemical impedance spectroscopy (EIS), Port. Electrochim. Acta., 2011, 29, 233–251. doi: 10.4152/pea.201104233

22. J.R. Macdonald and E. Barsoukov, Impedance spectroscopy: Theory, experiment, and applications, History, 2005, 1, 1–13.

23. A.I. Shcherbakov, I.G. Korosteleva, I.V. Kasatkina, V.E. Kasatkin, L.P. Kornienko, V.N. Dorofeeva, V.V. Vysotskii and V.A. Kotenev, Impedance of an Aluminum Electrode with a Nanoporous Oxide, Prot. Met. Phys. Chem. Surf., 2019, 55, 689–694. doi: 10.17675/2305-6894-2021-10-1-10

24. E. Kondoh ELLIPSHEET: Spreadsheet Ellipsometry (Excel Ellipsometer). EXCEL Worksheets for Basic Ellipsometry Calculation. https://www.ccn.yamanashi.ac.jp/~kondoh/ellips_e.html

25. D.A. Shirley High-resolution X-ray photoemission spectrum of the valence bands of gold, Physical Review B, 1972, 5.

26. A.Yu. Luchkin, O.A. Goncharova, D.S. Kuznetsov, I.V. Tsvetkova, O.S. Makarova, D.M. Sudorgin, S.S. Vesely and N.N. Andreev, Screening of individual organic compounds as chamber corrosion inhibitors, Int. J. Corros. Scale Inhib., 2022, 11, 1, 257–265. doi: 10.17675/2305-6894-2021-11-1-14

27. L.I. Antropov, Formal theory of the action of organic corrosion inhibitors, Zashch. Met.,1977, 13, 387–399.

28. Л.И. Антропов, Е.М. Макушин и В.Ф. Панасенко, Ингибиторы коррозии металлов, Киев: Технiка. 1981, 183 c.

29. Laure Caracciolo, Lénaïc Madec, Hervé Martinez. XPS Analysis of K-based Reference Compounds to Allow Reliable Studies of Solid Electrolyte Interphase in K-ion Batteries. ACS, Applied Energy Materials. 2021, 4, 10, 11693–11699. doi: 10.1021/acsaem.1c02400