Abstract
Thiourea derivatives namely, phenylthiourea (PTU), N, N′-diphenylthiourea (DPTU) and N-naphtyl N′-phenylthiourea (NPTU) synthesised in our laboratory, were tested as inhibitors for the corrosion of cold rolled steel in 1 M HClO4 using polarisation and electrochemical impedance measurements. At 30 °C, PTU and DPTU stimulated corrosion at low concentrations while addition of NPTU caused inhibition at all concentrations. The best protection (93%) was obtained by adding NPTU at 2.5 × 10−4 M. Polarisation curves showed that NPTU acted as a mixed inhibitor. The degree of surface coverage of the adsorbed inhibitors was determined by the ac impedance technique. The adsorption of NPTU on the cold rolled steel surface obeyed the Langmuir adsorption isotherm. Corrosion behaviour in the presence of NPTU at various concentrations was studied in the temperature range 20–50 °C. Both the corrosion rate of cold rolled steel and protection efficiency increased with increasing temperature. Activation energies with and without NPTU were obtained from the temperature dependence of corrosion current. The thermodynamic functions of the adsorption processes were calculated from the polarisation data and were used to analyse the inhibitor adsorption mechanism.
Similar content being viewed by others
References
Tang L, Li X, Li L, Qing Q, Mu G, Liu G (2005) Mater Chem Phys 94:353
Benchekroun K, Delard F, Rameau JJ, El Ghazali A (2002) New J Chem 26:153
Bentiss F, Traisnel M, Chaibi N, Mernari B, Vezin H, Lagrenée M (2002) Corros Sci 44:2271
Popova A, Sokolova E, Raicheva S, Christov M (2003) Corros Sci 45:33
Chetouani A, Hammouti B, Benhadda T, Daoudi M (2005) Appl Surf Sci 249:375
Gopi D, Bhuvaneswaran N, Rajeswarai S, Ramadas K (2000) Anti-Corros Meth Mater 47:332
Larabi L, Benali O, Harek Y (2007) Mater Lett 61:3287
Larabi L, Benali O, Mekelleche SM, Harek Y (2006) J Mater Sci 41:7064
Quraishi MA, Ansari FA, Jamal D (2002) Mater Chem Phys 77:687
Özcan M, Dehri I, Erbil M (2004) Appl Surf Sci 236:155
Hackerman N, Cook EL (2001) J Electrochem Soc 97:3
Ahlberg A, Friel M (1989) Electrochim Acta 34:190
Agrawal R, Namboodhiri TKG (1990) Corros Sci 39:39
Ateya BG, El-Anadouli BE, El-Nizamy FM (1984) Corros Sci 24:497
Cheng VL, Ma HY, Chen SH, Yu R, Chen X, Yao ZM (1999) Corros Sci 41:321
Raicheva SN, Aleksiev BV, Sokolova EI (1993) Corros Sci 34:343
Lawsson MB (1980) Corrosion 36:493
Pillai KC, Narayan R (1978) J Electrochem Soc 125:1393
Iofa ZA, Batrakov VV, Cho-Ngok-Ba (1964) Electrochim Acta 9:1645
Oudar J (1990) Br Corros J 25:21
Oldham HG (1989) In: Danami LA (ed) Sulfur containing drugs and related organic compounds, chemistry, biochemistry and toxicology, vol 2 (Part B). Ellis Harwood Limited, Chichester, p 9
Stoynov ZB, Grafov BM, Savova-Stoynova B, Elkin VV (1991) Electrochemical impedance. Nauka, Moscow
Growcock FB, Jasinski RJ (1989) J Electrochem Soc 136:2310
Rammelt U, Reinhard G (1987) Corros Sci 27:373
Pang J, Briceno A, Chander S (1990) J Electrochem Soc 137:3447
Stoynov Z (1990) Electrochim Acta 35:1493
Macdonald JR (1987) J Electroanal Chem 223:233
Lopez DA, Simison SN, De Sanchez SR (2003) Electrochim Acta 48:845
Popova A, Christov M (2006) Corros Sci 48:3208
Wu X, Ma H, Chen S, Xu Z, Sui A (1999) J Electrochem Soc 146:1847
Ma H, Chen S, Yin B, Zhao S, Liu X (2003) Corros Sci 45:867
Ivanov ES (1986) Inhibitions for metal corrosion in acid media. Metallurgy, Moscow
Szauer T, Brandt A (1981) Electrochim Acta 26:1209
Foroulis ZA (1990) Proceedings of the 7th European corrosion inhibitors, Ferrara, p 149
Gomma GK (1998) Mater Chem Phys 55:131
Bockris O’M J, Swinkels DAJ (1964) J Electrochem Soc 111:736
Bockris O’M J, Drazic D (1962) Electrochim Acta 7:293
Branzoi V, Branzoi F, Baibarac M (2000) Mater Chem Phys 65:288
El-Etre AY (2001) Corros Sci 43:1031
Durnie W, De Marco R, Kinsella B, Jefferson A (1999) J Electrochem Soc 146:1751
Khamis E (1990) Corrosion 46:476
Amar H, Benzakour J, Derja A, Villemin D, Moreau B, Braisaz T (2005) Appl Surf Sci 252:6162
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Benali, O., Larabi, L. & Harek, Y. Adsorption and inhibitive corrosion properties of thiourea derivatives on cold rolled steel in 1 M HClO4 solutions. J Appl Electrochem 39, 769–778 (2009). https://doi.org/10.1007/s10800-008-9717-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10800-008-9717-x