TY - JOUR
T1 - Synthesis and corrosion inhibition of α-amino acids alkylamides for mild steel in acidic environment
AU - Olivares-Xometl, O.
AU - Likhanova, N. V.
AU - Domínguez-Aguilar, M. A.
AU - Arce, E.
AU - Dorantes, H.
AU - Arellanes-Lozada, P.
N1 - Funding Information:
O. Olivares-Xometl would like to thank CONACYT for the scholarship awarded to carry out postgraduate studies and to the BUAP-FIQ. N.V. Likhanova and M.A. Dominguez-Aguilar would like to thank the Programa de Ingeniería Molecular of the IMP and CONACYT. E. Arce is due to COFAA-EDI-IPN and SNI for the fellowships provided.
PY - 2008/8/15
Y1 - 2008/8/15
N2 - New compounds of alkylamides derived from α-amino acids were tested as corrosion inhibitors for carbon steel in an aqueous solution of hydrochloric acid. The chemical synthesis of these amides performed by aminolysis of α-amino acid methyl esters resulted in good yields. Electrochemical testing was carried out using polarization scans and weight loss measurements. Polarization scans indicated that compounds act as mixed corrosion inhibitors with an efficiency of 80-90% when dissolved in the testing solution at ≥50 ppm, whereas gravimetric results displayed a similar tendency. Microtox testing indicated a correlation with the molecular structure of inhibitors. Apparently, a long aliphatic chain (C > 12) promoted not only higher corrosion efficiency, but also a higher toxicity. The higher efficiency of dodecyl amine of tyrosine was apparently derived from its longer aliphatic chain, with some contribution from its phenyl ring, which reinforces the molecular interactions of π type bonding to the d orbital metal favouring film formation.
AB - New compounds of alkylamides derived from α-amino acids were tested as corrosion inhibitors for carbon steel in an aqueous solution of hydrochloric acid. The chemical synthesis of these amides performed by aminolysis of α-amino acid methyl esters resulted in good yields. Electrochemical testing was carried out using polarization scans and weight loss measurements. Polarization scans indicated that compounds act as mixed corrosion inhibitors with an efficiency of 80-90% when dissolved in the testing solution at ≥50 ppm, whereas gravimetric results displayed a similar tendency. Microtox testing indicated a correlation with the molecular structure of inhibitors. Apparently, a long aliphatic chain (C > 12) promoted not only higher corrosion efficiency, but also a higher toxicity. The higher efficiency of dodecyl amine of tyrosine was apparently derived from its longer aliphatic chain, with some contribution from its phenyl ring, which reinforces the molecular interactions of π type bonding to the d orbital metal favouring film formation.
KW - Acidic medium
KW - Carbon steel
KW - Corrosion inhibition
KW - Protection efficiency
UR - http://www.scopus.com/inward/record.url?scp=43049115782&partnerID=8YFLogxK
U2 - 10.1016/j.matchemphys.2008.02.010
DO - 10.1016/j.matchemphys.2008.02.010
M3 - Artículo
SN - 0254-0584
VL - 110
SP - 344
EP - 351
JO - Materials Chemistry and Physics
JF - Materials Chemistry and Physics
IS - 2-3
ER -