Enhanced corrosion inhibition effect of tannic acid in the presence of gallic acid at mild steel/HCl acid solution interface

다국어 초록 (Multilingual Abstract)

The corrosion inhibition behaviour of tannic acid (TA), gallic acid (GA) and their blends on mild steel in 1 M HCl solution was studied via electrochemical methods, namely, polarization (Tafel plots) and electrochemical impedance spectroscopy (EIS). The surface morphology of mild steel in 1 M HCl, TA alone, and in combination with GA was elucidated using scanning electron microscopy (SEM). The results show that TA can protect mild steel from acid corrosion better than GA. However, inhibition effect of TA can be enhanced by its combination with GA. The adsorption behaviour of TA against steel corrosion obeyed Langmuir adsorption isotherm. Furthermore, polarization results suggest that TA and GA blends behaves as mixed-type inhibitor of predominant anodic effect. EIS results reveal that the charge transfer resistance value of the steel inhibited by TA in combination with GA is significantly higher than that of steel inhibited by TA alone. The SEM images confirmed the enhanced film formation on the steel surface in the presence of TA and GA blended in the ratio 9:1 when compared with TA alone.
Quantum chemical calculations have been used to provide insights into the mechanism of interaction of TA and GA on mild steel.

참고문헌 (Reference)

1 I. B. Obot, 52 : 198-, 2010

2 I. B. Obot, 83 : 359-, 2014

3 E. Stupnisˇek-Lisac, 47 : 4189-, 2002

4 I. B. Obot, 1 : 431-, 2013

5 M. A. Quraishi, 122 : 114-, 2010

6 M. M. Kabanda, 8 : 10839-, 2013

7 L. C. Murulana, 51 : 13282-, 2012

8 E. E. Ebenso, 51 : 12940-, 2012

9 S. K. Shukla, 7 : 5057-, 2012

10 A. R. Afidah, 1 : 223-, 2008

11 M. A. Hegazy, 81 : 54-, 2014

12 M. K. Awad, 959 : 66-, 2010

13 M. M. Kabanda, 7 : 5035-, 2012

14 B. Qian, 72 : 1-, 2013

15 M. Behpour, 131 : 621-, 2012

16 H. P. Wang, 64 (64): 347-, 2013

17 A. K. Satapathy, 51 : 2848-, 2009

18 D. K. Yadav, 51 : 14966-, 2012

19 R. F. V. Villamil, 472 : 112-, 1999

20 E. E. Oguzie, 310 : 90-, 2007

21 I. B. Obot, 50 : 2098-, 2011

22 N. O. Obi-Egbedi, 1002 : 86-, 2011

23 E. E. Ebenso, 7 : 5643-, 2012

24 N. O. Obi-Egbedi, 7 : 5649-, 2012

25 I. B. Obot, 122 : 325-, 2010

26 D. B. Hmamou, 52 : 14315-, 2013

27 D. B. Hmamou, 9 : 120-, 2014

28 K. M. Manamela, 9 : 3029-, 2014

29 E. Kusmierek, "Tannic acid as corrosion inhibitor for metals and alloys" 2013

30 M. J. Frisch, "Gaussian 03W" Gaussian Inc. 2004

31 I.B. Obot, "Anti-corrosive properties of xanthone on mild steel corrosion in sulphuric acid: Experimental and theoretical investigations" 한국물리학회 11 (11): 382-392, 2011