Research Journal of Chemical Sciences ______________________________________________ ISSN 2231-606X Vol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 87 Review PaperCorrosion inhibition study of Stainless steel in Acidic medium – An OverviewP.Selvakumar1,*, B.Balanaga Karthik and C.ThangaveluDepartment of chemistry, Chettinad college of Engineering and Technology, Karur- 639114, Tamilnadu, INDIA Department of Chemistry, Periyar EVR College (Autonomous), Tiruchirapalli – 620023, Tamilnadu, INDIA Available online at: www.isca.in Received 4th March 2013, revised 22nd March 2013, accepted 12th April 2013Abstract Inhibition of corrosion with different types of stainless steel, medium and inhibitors has been reviewed. Corrosion can be controlled or minimized by the use of inhibitors. Acids are frequently used to remove such scales including hydrochloric acid (HCl), sulphuric acid (HSO), sulfamic acid (HNSO) and phosphoric acid (HPO). There is a continuous search for better corrosion inhibitors to meet the need of the industrial expectations. The inhibition’s efficiency of inhibitor compounds is strongly dependent on the structure and the chemical properties of the film formed on the metal surface. The adsorption of inhibitors on the metal surface through polar atoms will prevent corrosion. The protection of metals from corrosion is analyzed by many technologies such as weight loss, Open Circuit Potential (OCP), Potentiodynamic Polarization, Electrochemical Impedance Spectra (EIS), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction spectroscopy (XRD), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscope (SEM), FTIR, UV-Visible spectra and adsorption study. Keywords: Stainless steel, acidic medium, corrosion inhibition, SEM. IntroductionStainless steel type 304 is widely used in many applications such as desalination plants, construction materials, pharmaceutical industry, thermal power plant, chemical cleaning and pickling process, due to their stability, good corrosion resistance, high strength, workability and weldability. Corrosion is the deterioration of essential properties of a material due to reactions with its surroundings. Millions of dollars are lost each year because of corrosion. Much of this loss is due to the corrosion of iron and steel although many other metals may corrode as well. Corrosion damage can cause leakage of fluids or gases. Even more dangerous is a loss of strength of the structure induced by corrosion and subsequent failure. The application of acid corrosion inhibitors in the industry is widely used to prevent or minimize material loss during contact with acid. It has been observed that the adsorption depends mainly on certain physico-chemical properties of the inhibitor molecule such as functional groups, steric factors, aromaticity, electron density at the donor atoms and orbital character of donating electrons and also on the electronic structure of the inhibitor. It has been reported that many inorganic, organic and heterocyclic compounds containing hetero atoms like N, O, S and P have been proved to be an effective inhibitors for the corrosion of stainless steel in acid media1-53. One way to protect the metal against corrosion is to add certain organic molecule that adsorb on the surface and form a protective layer. The unique advantage of the possibility of adding inhibitors is that this can be done without disruption of the industrial process. Corrosion inhibitors are useful when this addition in small amount prevent corrosion. At higher concentrations of organic compounds added additional testing for environmental impact is required 1-2. Metals: Different inhibitors have been used to control the corrosion of stainless steel metals with different grade such as 4103,53, AISI 30410-13,15,17,18,24-29,31,33,35,42,48,50,52, AISI 304L14,23,37,45, AISI 3164,11,20,27,29,43, AISI 316L 14,16,19,22,40,41,44,45,51, UNSS31603, 0Cr13, 1Cr13, 30230,36, ASTM 42032, 43034,38,39, Austenitic stainless steel47, stainless steel21,46,49, and iron12. Medium: In this overview my research is mainly focused on acidic medium such as sulphuric acid and hydrochloric acid. But few of the works carried out in the medium such as pure water, ground water, sea water, sodium chloride, sodium sulfate and sodium sulfide are used for this purpose. Additives: Various inhibitors have been used as corrosion inhibitor alone or combination with additive such as HEDP, ATMP, Zn2+ 9,24,53, Tween 809,24, Potassium iodide49and Potassium thiocyanide35. Methods: Different methods have been used to determine the inhibition efficiency of different inhibitors by Weight loss3,10,17,33,35,36,38,43,48,49,52,53, Gravimetric test27,29, Potentiodynamic Polarization3,5,6,8,13-19,21-23,27-31,37,39,40-42,44-52, Potentiostatic Polarization7,10,33,36, Galvanostatic Polarization 13,25,35,38, Linear Polarization26,32,47, Cyclic Polarization 15,32, Cyclic voltametry11,12,14,26,44, Gasometry, Current Transient Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 88 Analysis21, Repassivation Potential21, AC impedance7,12,33,53, Electrochemical Impedance Spectroscopy11,16,18,23,27,28,41,45,46,50,52, Open Circuit Potential 11,12,15,30,31,40,44,51, Temperature dependent pitting potential and Synergistic effect35,49 has been analyzed. Surface AnalysisA protective film is confirmed by various surface examination techniques such as SEM3,14,20-24,26,27,29,37,38,40,41,44,45,53, XRD9,24,45, FTIR9,24,26, EDX14,22,27,29,38, XPS20,21,24,27,32,34,37, X-ray mapping29, surface reflectance – IR spectroscopy 20, X-ray photo electron 34, AFM53 and Luminescence spectroscopy 9,24. Adsorption StudyThe adsorption behavior of different inhibitors on the stainless steel surface has been investigated. The following adsorption isotherms have been obeyed such as Langmuir3,6,8,10,14,17,19,25,28,33,36,39,47,52, Frumkin7,9, Freundlich49, Tempkin30,38,42,48,50 and Dubininradushkevich adsorption isotherm47. A list of corrosion inhibition studies performed in different type of stainless steels is shown in table–1. Table-1 List of Corrosion inhibition studies of Stainless steel S. No Metal Medium Inhibitor Additive Methods Findings Ref Year 1 410 Stainless steel 1 N SOThiourea, Allylthiou rea and n-Phenylthiourea Weight loss, PotentiodynamicPolarisation, SEM and adsorption study. It shows better inhibition in the following order n-Phenylthiourea �Allylthiurea� TU. A protective layer is confirmed by SEM and it obeys Langmuir adsorption isotherm. 3 1990 2 AISI 304 and AISI 316 Stainless steel 0.1 M and 0.5 M NaCl 0.01 M and 0.1 M Molybdate Temperature dependent pitting potential. It shows better inhibition for both alloys. 4 1991 3 UNS S31603 stainless steel 0.6 M NaCI + 0.1 M NaSOCerium PotentiodynamicPolarisation, Adsorption study. It is an excellent inhibitor. Thermodynamic data suggests that the highly stable cerium oxide is responsible for blocking the active sites during cathodic and anodic reactions. 5 1993 4 1Cr13 Stainless steel 0.1 M SOATMP (aminotrimethylenephosphonic acid), MADMP (methylaminodimethylenephosphonic acid), BADMP (n-butyl-aminodimethylenephosphonic acid) and HEDP (1-hydroxyethylidene 1, 1-diphosphonic acid) Potentiodynamic Polarization and adsorption study. It shows Mixed type of corrosion inhibitors, Their adsorption obeys the Langmuir isotherm equation 6 1994 5 AISI 304 Stainless steel 2 M SO2- Methyl benzoazole derivative Weight loss, Gasometry, PotentiostaticPolarisation, AC impedance and adsorption study. It shows excellent inhibitor. The stability of film formed was verified and it obeys the Frumkin isotherm. 7 1998 6 0Cr13 Stainless steel 0.1 M SOSADP (N-sulfonic amino-dimethylenephosphonicacid) HEDP (1-hydroxyethylidene-1, 1-diphosphonic acid) and ATMP (aminotrimethylenephosphonic acid) Potentiodynamic Polarization and adsorption study. It was found to be an efficient inhibitor for acid corrosion and it obeys Langmuir adsorption isotherm. The corrosion inhibition efficiency may be high in the following order. SADP�ATMP�HEDP Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 89 7 AISI 304 austenitic stainless steel Ground Water 3-phosphonopropionic acid Zn2+ and Tween 80 (polyoxyethylenesorbitanmonooleate) Luminescence, XRD, FTIR and SEM. It shows Mixed type of inhibitor and a protective layer is confirmed by SEM and FTIR. 9 2002 8 AISI 304 Stainless steel 1.0 M HCl Rhodanineazosulpha drugs Weight loss, PotentiostaticPolarisation and adsorption study. It is a mixed type excellent inhibitor and it obeys the Langmuir adsorption isotherm. 10 2002 9 AISI 316 and AISI 304 Stainless steel 0.5 M HCl and SOPolyanilineandPoly(o-methoxyaniline) Open Circuit Potential (OCP), Cyclic voltametry, Impedance Spectroscopy (EIS). Potential value move towards positive direction and it shows better inhibition, a protective layer is confirmed by impedance spectra. 11 2002 10 AISI 304 stainless steel and Iron 0.01 M NaCl Tungstate Open Circuit Potential, Cyclic voltametry, AC impedance spectroscopy. Potential value move towards positive direction and it shows better inhibition. 12 2003 11 AISI 304 Stainless steel 0.5 M SO4-Substituted pyrazole-5-ones Potentiodynamic and GalvanostaticPolarisation and mechnism of inhibition. It is an excellent inhibitor. 13 2003 12 AISI 304L and AISI 316 L Stainless steel 0.5 M HCl and SO(MBO) 2-Mercaptobenzoxazole PotentiodynamicPolarisation, Cyclic voltametry, EDX, SEM, and adsorption study. It is an excellent inhibitor. It obeys the Langmuir adsorption isotherm and the formation of passive film is confirmed. 14 2004 13 AISI 304 Stainless steel Pure Water Oxyanions tungstate and molybdate Open Circuit Potential (OCP), PotentiodynamicPolarisation and Cyclic Polarisation. Potential value move towards positive direction and it shows better inhibition at higher temperatures. 15 2004 14 AISI 316L Stainless steel Acidic Alkaline solution of 0.3 M NaCland pH 4,8 and 10 Indole PotentiodymanicPolarisation and Electrochemical Impedance Spectra(EIS). It has proven to be efficient inhibitor. Indole was found to have no significant efficiency on the corrosion of the metal in alkaline solutions. 16 2004 15 AISI 304 Stainless steel 15% HCl N-[(Z)-1-Phenylemethyleidene]-N-{2-[(2-{[(Z)-1 phenylmethylidine] amino}phenyl)disulfanyl] phenyl} amine Weight loss, PotentiodynamicPolarisation, Impedance Spectroscopy (EIS) and adsorption study. It is a mixed type excellent inhibitor and it obeys the Langmuir adsorption isotherm. 17 2005 16 AISI 304 stainless steel 0.5 M SOThiphene derivatives PotentiodynamicPolarisation, Impedance Spectroscopy(EIS) It is a mixed type excellent inhibitor and a protective layer is confirmed. 18 2005 17 AISI 316L Stainelss steel 75 g/L SO+ 25g/L HF + 3-Hydroxybenzoic acid PotentiodynamicPolarisation, and adsorption study. It is an excellent inhibitor and obeys the Langmuir andFrumkin adsorption isotherm. 19 2005 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 90 30g/L 2 O 2 18 AISI 316 Stainless steel 0.5 M SO2-thiophene carboxylic hydrazide (TCH) Surface reflectance IR spectroscopy, XPS and SEM It is an excellent inhibitor. A protective layer is confirmed by XPS and SEM. 20 2005 19 Stainless steel 0.02 M NaCl Copper Current transient analysis, Polarization, repassivation potential measurements, XPS and SEM. Copper reduces steel dissolution rates in acidic chloride medium and a protective layer is confirmed by XPS and SEM. 21 2005 20 AISI 316L Stainless steel 0.5 M NaCl 2-Mercaptobenzimidazole PotentiodynamicPolarisation, EDX, SEM and adsorption study. It is an efficient inhibitor, breakdown potential move towards positive direction, and the negative values of activation energy indicates spontaneous adsorption . 22 2006 21 AISI 304L Stainless steel 1 M SOCysteine PotentiodymanicPolarisation, Electrochemical Impedance Spectra and SEM. It proves better inhibition and it forms a protective layer on the metal surface. 23 2006 22 AISI 304 Stainless steel Ground Water (Amino trimethylenephosphonic acid) ATMP Zn2+ along with Tween 80 (polyoxyethylenesorbitanmonooleate) Luminescence Spectra, FTIR Spectra, XRD, XPS and SEM. To understand the mode of corrosion inhibition and also the morphological changes on the metal surface 24 2007 23 AISI 304 Stainless steel 0.1 M HCl Pyrimidine derivatives GalvanostaticPolarisation, adsorption study. It is a mixed type of inhibitor and it obeys the Langmuir adsorption isotherm. 25 2007 24 AISI 304 Stainless steel 0.5 M HCl and 0.5 M NaCl Poly(N-ethylaniline) Linear Anodic Polarisation, Cyclic voltametry, FT-IR Spectroscopy and SEM. It is an excellent inhibitor and a protective layer is confirmed by FT-IR, SEM. 26 2008 25 AISI 316 and AISI 304 Stainless steel 30 wt% SOMo and Mn Gravimetric test, Polarisation, Impedance Spectroscopy(EIS), SEM, EDX and XPS. It shows excellent inhibitor, A protective layer is confirmed by SEM, EDX, and XPS. 27 2008 26 AISI 304 Stainless steel 0.1 M SO1,2,3-benzotriazole (BTAH) Potentiodynamic Polarization curves, Electrochemical Impedance Spectroscopy (EIS) and adsorption study. It was found to be an efficient inhibitor for acid corrosion and it obeys Langmuir adsorption isotherm. 28 2008 27 AISI 304 and AISI 316 Stainless steel 3.5 wt % NaCl and 6wt % FeClMn and Mo Gravimetric tests, PotentiodynamicPolarisation, SEM, X-ray mapping and EDX. It proves better inhibition. It forms a protective layer on the metal surface and it is confirmed by SEM and EDX. 29 2008 28 302 Stainless steel 1M HCl and 1M 2 SO 4 MPT (1-methyl -3 Pyridine -2-yl-thiourea Open Circuit potential(OCP), PotentiodynamicPolarisation, Adsorption study. Formation of passive films, inhibitor follows Tempkin adsorption isothem. 30 2009 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 91 29 AISI 304 Stainless steel 1.5% NaCl Ciprofloxacin andNorfloxacin Open Circuit potential(OCP), PotentiodynamicPolarisation. It is a anodic type of inhibitor and a potential becomes positive direction. 31 2009 30 ASTM 420 Stainless steel 3% NaCl Polyethyleneimine Linear, Cyclic Polarisation, and XPS. Proves that it is a very good inhibitor in pitting corrosion and a protective layer is confirmed by XPS. 32 2009 31 AISI 304 Stainless steel 1 M HCl Bis-N,S-bidentate Schiff base Weight loss, PotentiostaticPolarisation, AC impedance and adsorption study. It is a mixed type excellent inhibitor and it obeys the Langmuir adsorption isotherm. 33 2009 32 AISI 430 stainless steel 3% NaCl polyethyleneimine. Linear Polarisation, Cyclic Polarisation and X-ray photoelectron spectroscopy (XPS) It proves better inhibition. It forms a protective layer on the metal surface and it is confirmed by XPS. 34 2009 33 AISI 304 Stainless steel 3.0 M HCl 4-phenylthiazole KSCN Weight loss, Synergistic effect, GalvanostaticPolarisation and adsorption study. It shows that it is an excellent inhibitor also higher temperature. Synergistic role existing between the inhibitors and it obeys Temkin’s adsorption isotherm and thermodynamic – kinetic model. 35 2009 34 302 Stainless steel 0.5M SO(BCBD) 2,2'-[bis - N(4-chlorobenzaldimine)-1.1' – dithio, (BAPD) bis - (2-amino phenyl) disulphide Weight loss, PotentiostaticPolarisation, Adsorption study. It is a mixed type of inhibitors. It obeys Langmuir adsorption isotherm. 36 2010 35 304L Stainless steel 0.9% NaCl Poly (Vinyl Alcohol) PotentiodynamicPolarisation, impedance spectroscopy, SEM, XPS. PVA act as a good inhibitor and it confirms a stable and uniform thin film formation. 37 2010 36 430 Stainless steel 2 M HCl Crown ethers Weight loss, Galvanostatic Polarization, SEM, EDX and adsorption study. It shows Mixed type of corrosion inhibitors. Protective layer is confirmed by SEM, EDX and obeys the Temkin adsorption isotherm. 38 2010 37 430 Stainless steel 0.1 M HCl N,N'-diquaternized 4,4'-dipyridinium salts PotentiodymanicPolarisation, adsorption study. It is a mixed type excellent inhibitor and it obeys the Langmuir adsorption isotherm. 39 2010 38 316L Stainless steel 0.5 M SOLysine (-diaminocaproic acid) Open circuit potential (OCP), PotentiodynamicPolarisation, and SEM. Potential value move towards positive direction, Lysine act as a good cathodic inhibitor. A protective film is confirmed by SEM 40 2011 39 316L Stainless steel 0.5 M SOTriazoloisoquinoline derivatives. PotentiodynamicPolarisation, EIS and SEM. A very good inhibitor. Hydrogen evolution rate is low by EIS anda protective film is confirmed by SEM. 41 2011 40 AISI 304 Stainless steel 2 N HCl N-Furfuryl N'-Phenyl Thiourea PotentiodynamicPolarisation, and adsorption study. It shows that it is an anodic inhibitor, it follows the Temkin's adsorption isotherm and 42 2011 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 92 the mechanism is followed by Physisorption. 41 AISI 316 Stainless steel 0.1 M HCl 2-(4-Methyl -3-oxo-2-phenyl-2, 3-dihydro - 1 H- pyrazolo[3, 4-b] pyridine -4-yl) acetic acid butylester Weight loss and adsorption study. It proves that it is an excellent inhibitor and it suggests that spontaneous adsorption takes place. 43 2011 42 AISI 316L Stainless steel 0.15 M NaCl Molybdate and Nitrate Open Circuit Potential(OCP), Polarisation, Cyclic voltametry and SEM. A potential value move towards positive direction and shows that it is a good inhibitor. A protective layer is confirmed by SEM. 44 2011 43 AISI 304L and AISI 316 L Stainless steel Oxygen free NaSO+ NaS at pH 3 S PotentiodynamicPolarisation, EIS, SEM and XRD. It is a better inhibitor for both alloys and a potential value move towards positive direction. A passive layer is confirmed by XRD and SEM. 45 2011 44 Stainless steel 1 N SOpoly-N-vinylimidazole and N-vinylimidazole Potentiodynamic Polarization, EIS and adsorption study. Shows that it is an excellent inhibitor. Thermodynamic data suggests that the highly stable layer is confirmed. 46 2011 45 Austenitic stainless steel 0.5 M SO5-benzoyl-4,6- diphenyl-1,2,3,4-tetrahydro-2-thiopyrimidin (DHPM I) and 5-Benzoyl-6-phenyl-4-p- tolyl-3,4-dihydropyrimidin-2(1H)-one (DHPM II). Potentiodynamic Polarization, Linear Polarization resistance (LPR), EIS andadsorpion study. It shows better inhibition, and obeys the Langmuir, Dubinin–Radushkevich adsorption isotherm. 47 2011 46 AISI 304 Stainless steel 2 N HCl N - (2-mercaptophenyl) -N' - phenyl Thiourea Weight loss, PotentiodynamicPolarisation andadsorption study. It is a mixed type of inhibitors. It obeys Temkin adsorption isotherm, and the inhibition is governed by physisorption mechanism. 48 2011 47 Stainless steel 1 M HCl Decylsulphate sodium salt (SSDS),Dodecylsulphate sodium salt (SSDDS),Hexadecylsulphate sodium salt (SSHDS), Dodecyl benzene sulfonate sodium salt (SSDDBS) Potassium Iodide (KI) Weight loss, Synergistic efect, PotentiodynamicPolarisation and adsorption study. It is a mixed type excellent inhibitor and it obeys the Freundlich adsorption isotherm. Synergistic role existing between the inhibitors. 49 2011 48 AISI 304 austenitic stainless steel 0.5 M SOhexadecylpyridinium bromide (HDPB) Potentiodynamic polarization, EIS and adsorption study. It is a mixed type excellent inhibitor and it obeys the Temkin adsorption isotherm. 50 2011 49 AISI 316L Stainless steel 1 M SOAMINIO ACIDS (Arginine. Glycine, Leucine and Valine) Open Circuit Potential(OCP), PotentiodynamicPolarisation. Glycine, Valine and Leucine act as corrosion inhibitors but Arginine act as corrosion accelerator. 51 2011 50 AISI 304 Stainless steel 1 M HCl Extract of Salvia officinalis Weight loss, Potentiodynamic Polarization, EIS and adsorption study. It shows Mixed type of corrosion inhibitors and their adsorption obeys the Langmuir isothem. 52 2012 51 410 Stainless steel Sea water Sodium Tungstate Zn2+Weight loss, AC impedance, SEMand AFM. It shows that excellent inhibitor and Protective film is confirmed. 53 2013 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 93 Conclusion Corrosion inhibition study on using stainless steel in acidic environment with various inhibitors and additives at room temperature has been reviewed. Electro chemical studies like Polarization, AC impedance and surface morphology such as Scanning Electron Microscope, Atomic Force Microscope and Fourier Transform infrared Spectroscopy have also been analyzed. AcknowledgementI would like to extend my heartiest gratitude to my management, friends and my family for providing moral support. References1.Bockris J.O.M. and Reddy A.K.N., Modern Electrochemistry 2B, Electrodics in chemistry, Engineering, biology and Environmental Science, second ed., Kluwer Academic plenum publishers, New York, 1703 2000) 2.Ashassi–Sorkhabi H., Asghari, Effect of hydrodynamic conditions on the inhibition performance of L-methionine as a green inhibitor, J. Electrochim Acta., 54, 162-167 20083.Reeta Agarwal and Namboodhiri T.K.G., The inhibition of sulphuric acid corrosion of 410 stainless steel by thioureas, J.Corros. Sci, 30, 37-52 (19904.Urgen M. and Cakir A.F., The Effect of Molybdate ions on the temperature dependent pitting potential of austenitic Stainless steel in neutral chloride solutions, J. Corros. Sci., 32, 841-852 (19915.Lu. Y.C. and Ives M.B., The improvement of the localized corrosion resistance of Stainless steel by cerium, J. Corros. Sci., 34, 1773-1785 (1993)6.Zhou Mingpeng, Wang Kaiming, DiaoYuemin and Zhou Bensheng, Corrosion inhibition of methylenephosphonic acids with R-N-[CHPO(OH) structure in sulpuric acid solution, J. Chinese Society of Corrosion and Protection., 14, 283-290 (19947.Al-Mayout A.M, Al-Suhybani A.A., Al-Ameery A.K., Corrosion inhibition of 304SS in sulphuric acid solutions by 2-methyl benzoazole derivatives, Desalination, 116, 25-33 (19988.Yang W.Z. and Zhou B.S., Study on corrosion inhibition by N-Sulfonic aminodimethylenephosphonicacid, J. Chinese Society of Corrosion and Protection, 20, 105-110 (2000)9.Gopi D. and Rajeswari S., Surface characterization and electrochemical corrosion behavior of 304stainless steel in aqueous media, J. Solid State Electrochemistry,, 194-202 (2002)10.Abdallah M., Rhodanine azosulpha drugs as corrosion inhibitors for corrosion of 304stainless steel in hydrochloric acid solution, J. Corros. Sci., 44, 717-728 (2002)11.Paul A. Kilmartin, Lissa Trier, Graham, A, Wright, Corrosion inhibition of polyaniline and poly (o-methoxyaniline) on stainless steels, Synthetic metals, 131, 99-109 (2002)12.Denise S., Azambuja Emilse M.A., Martini and Iduvirges L. Muller, Corrosion behavior of Iron and AISI 304 stainless steel in Tungstate Aqueous solutions containing chloride, J. Braz.Chem.Soc., 14, 570-576 (2003)13.Abdallah M., Corrosion behavior of 304stainless steel in sulphuric acid solutions and its inhibition by some substituted pyrazolones, Materials Chemistry and Physics, 82, 786–792 (2003)14.Refaey S.A.M., Taha F., Abd El-Malak A.M., Inhibition of stainless steel pitting corrosion in acidic medium by 2-mercaptobenzoxazole, Applied Surface Sci., 236, 175–185 (2004)15.Celeste Rabacal Alentejano, Idalina Vieira Aoki, Localized corrosion inhibition of 304stainless steel in pure water by oxyanions tungstate and molybdate, Electrochemica Acta., 49, 2779-2785 (2004)16.Meltem Dudukcu, Birgul Yazici, Mehmet Erbil, The effect of indole on the corrosion behaviour of stainless steel, Materials Chemand Phy., 87, 138–141 (2004)17.Behpour M., Ghoreishi. S.M., Mohammadi N., SalavatiNiasari.MN-[(Z)-1-Phenylemethyleidene]-N-{2-[(2-{[(Z)-1 phenylmethylidine]amino}phenyl)disulfanyl] phenyl} amine and its derivatives on the corrosion of stainless steel 304 in acid media, J. Corros. Sci., 53, 3380-3387 (2005)18.Galal A., Atta N.F., Al-Hassan M.H.S., Effect of some thiophene derivative on the electrochemical behaviour of AISI 316austenitic stainless steel in acidic solutions containing chloride ions, I. Molecular structure and inhibition efficiency relationship, Materials Chem and Phy., 89, 38-48 (2005)19.Narvaez L., Cano E. and Bastidas D.M., 3-Hydroxybenzoic acid as AISI 316Lstainless steel corrosion inhibitor in a SO-HF-H pickling solution, J.Applied Electrochemistry, 35, 499-506 (2005)20.Galal A., Atta N.F., Al-Hassan M.H.S., Effect of some thiophene derivatives on the electrochemical behavior of AISI 316austenitic stainless steel in acidic solutions containing chloride ions II, Effect of temperature and surface studies, Materials Chem and Phy., 89, 28–37 200521.Sourisseau T., Chauveaub E. and Barouxa B., Mechanism of copper action on pitting phenomena observed on stainless steels in chloride media, J. Corros. Sci., 47, 1097–1117 (2005 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 94 22.Refaey S.A.M., Taha F., Abd El-Malak A.M., Corrosion and inhibition of 316Lstainless steel in neutral medium by 2-Mercaptobenzimidazole, Int. J.Electrochem. Sci., , 80-91 (2006)23.Silva A.B., Agostinho S.M.L., Barcia O.E., CordeiroG.G.O. and E. D’Elia, The effect of cysteine on the corrosion of 304L stainless steel in sulphuric acid, J. Corros. Sci, 48, 3668–3674 (2006)24.Gopi D., Manimozhi S., Govindaraju K.M., Manisankar P. and Rajeswari S., Surface and electrochemical characterization of pitting corrosion behaviour of 304stainless steel in ground water media, J. Applied Electrochemistry, 37, 439-449 (200725.Fouda A.S. and El-Dafrawy H., Inhibitive effect of some pyrimidine derivatives on the cyclic stressed specimens of stainless steel type 304 in acidic media, Int.J. Electrochem. Sci., , 721-733 (200726.Aziz Yagan Nuran Ozcicek Pekmez, Attila Yildiz, Poly(N-ethylaniline) coatings on 304stainless steel for corrosion protection in aqueous HCl and NaClsolutions. Electrochemica Acta., 53, 2474-2482 (200827.Pardo A., Merino M.C., Coy A.E., Viejo F., Arrabal R. and Matykina E., Effect of Mo and Mn additions on the corrosion behaviour of AISI 304 and 316stainless steels in SO4, Corros. Sci., 50, 780-794 (200828.Satpati. A.K, Ravindran. P.V, Electrochemical study of the inhibition of corrosion of stainless steel by 1,2,3benzotriazole in acidic media. Materials Chem and Phy109, pp.352–359 (200829.Pardo. A, Merino. M.C, Coy. A.E, Viejo. F, Arrabal. R, Matykina. E, Pitting corrosion behaviour of austenitic stainless steels – combining effects of Mn and Mo additions. J. Corros. Sci.50, pp.1796–1806 (200830.Hosseini S.M.A. and Salari M., Corrosion inhibition of stainless steel 302 by 1-methyl-3-pyridine-2-yl-thiourea in acidic media, Indian J. Chemical technology, 16, 480-485 (2009)31.Dubey R.S. and Yogesh Potdar, Corrosion inhibition of 304stainless steel in sodium chloride by ciprofloxacin and norfloxacin, Indian J. Chemical technology, 16, 334-338 (2009)32.Matjaz Finsgar, Stefan Fassbender, Fabio Nicolini, Ingrid Milosev, Polyethyleneimine as a corrosion inhibitor for ASTM 420Stainless steel in near neutral saline media, J. Corros Sci., 51, 525-533 (2009)33.Behpour M., Ghoreishi S.M., Soltani N. and SalavatiNiasari M., The inhibitive effect of some bis- N,S-bidentate Schiff bases on corrosion behaviour of 304stainless steel in hydrochloric acid solution, J. Corros Sci., 51, 1073–1082 200934.MatjazFinsgar, Stefan Fassbender, Sabine Hirth, Ingrid Milosev, Electrochemical and XPS study of polyethyleneimines of different molecular sizes as corrosion inhibitors for AISI 430stainless steel in near-neutral chloride media, Materials Chem and Phy., 116, 198–206 (2009)35.Fouda. A.S, Ellithy. A. S, Inhibition effect of 4-phenylthiazole derivatives on corrosion of 304L stainless steel in HCl solution, J. Corros. Sci.51, 868–875 (2009)36.Hosseini. S.M.A, Azim. A, Sheikhsoaei. I, Salari. M, Corrosion inhibition of 302Stainless steel with schiff base compounds, J. Iran. Chem. Soc., , 779-806 (2010)37.Samide A., Ciuciu A. and Negrila C., Surface analysis of inhibitor film formed by Poly(Vinyl Alcohol) on stainless steel in sodium chloride solution, Portugaliae Electrochemica Acta., 28, 385-396 (2010)38.Fouda A.S., Abdallahb M., Al-Ashreya S.M. and AbdelFattahb A.A., Some crown ethers as inhibitors for corrosion of stainless steel type 430 in aqueous solutions, Desalination, 250, 538–543 (201039.Al-Nowaiser F.M., Corrosion Inhibition of Type 430Stainless Steel in HCl Solution by Dipyridinium Salts, J. King Abdulaziz University Sci., 22, 89-100 (2010)40.Azza EI, Sayed EI, Shenway, Corrosion inhibition of lysine as basic amino acids on 316L stainless steel in 0.5M HSOsolution, J. American Sci., , 600-605 (2011)41.Nada F. Atta A.M. Fekry, Hamdi M. Hassaneem, Corrosion inhibition, hydrogen evoluation and antibacterial properties of newly synthesized organic inhibitors on 316L stainless steel alloy in acidic medium, International J. hydrogen energy., 36, 6462-6471 (2011)42.Herle R., Shetty P., Shetty S.D. and Kini U.A., Corrosion inhibition of 304SS in Hydrochloric acid solution by N-Furfuryl N'-Phenyl Thiourea, Portugaliae Electrochimica Acta., 29, 69-78 (2011)43.James O.O., Ajanaku K.O., Ogunniran K.O., Ajani O.O., Siyanbola T.O. and John M.O., Adsorption Behaviour of pyrazolo [3, 4-b] pyridine on corrosion of stainless steel in HCl solution, Trends in Applied Sciences Research., , 910-917 (201144.Gonzalez. M.B, Saidman. S.B, Electrodeposition of polypyrrole on 316L stainless steel for corrosion prevention, J. Corros. Sci., 53, 276-282 (201145.Davoodi A., Pakshir M., babaiee M. and Ebrahimi G.R., A comparative study of 304L and 316L stainless steel in acidic media, J. Corros. Sci., 53, 399-408 (201146.AysegulOncul, KerimCoban, EsmaSezer, Bahire Filiz Senkal. Inhibition of the corrosion of stainless steel by poly-N-vinylimidazole and N-vinylimidazole, Progress in Organic Coatings, 71, 167–172 (2011 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 87-95, April (2013) Res. J. Chem. Sci. International Science Congress Association 95 47.NeclaCaliskan, EsvetAkbas, The inhibition effect of some pyrimidine derivatives on austenitic stainless steel in acidic media, Materials Chem and Phy., 126, 983–988 (201148.RamadevHerle, Prakash Shetty, Divakara Shetty. S, AchuthaKini. U, Corrosion Inhibition of Stainless Steel in Hydrochloric Acid by N - (2-mercaptophenyl) -N' -phenyl Thiourea, International J. Chemistry and Applications, , 151-158 (2011)49.Diwan Singh Rajan, Shiv Darshan Malik, Surfactants as Corrosion Inhibitors for Stainless Steel in HCl Solution, J. Pure and Applied Science and Technology, , 23-35 (2011)50.Hamza M.M., Abd El Rehim S.S., Magdy, Ibrahim. A.M. Inhibition effect of hexadecylpyridinium bromide on the corrosion behavior of some austenitic stainless steels in SOsolutions, Accepted in Arabian Journal of Chemistry, ARTICLE IN PRESS 51.Abdel Ghanyl N.A., The Inhibitive Effect of some amino acids on the corrosion behaviour of 316L stainless steel in sulphuric acid Solution, Modern Applied Science,, 19 (2011)52.Nasrin Soltani, Nahid Tavakkoli, Maryam Khayatkashani, Mohammad RezaJalali and Ahmad Mosavizade, Green approach to corrosion inhibition of 304stainless steel in hydrochloric acid solution by the extract of Salvia officinalisleaves,J. Corros. Sci., 62, 122–135 (2012)53.Patric Raymond P., Peter Pascal Regis A., Rajendran S. and Manivannan M., Investigation of Corrosion Inhibition of Stainless steel by Sodium tungstate, Res. J. Chem. Sci., 3(2), 54–58 (2013)