1Periyar E. V. R. College, Trichirappalli, 620023, Tamilnadu, India
2St. Joseph's College, Trichirappalli, 620002, Tamilnadu, India
3Servite College of Education Thogaimalai, Tamilnadu, India
4Gandhigram Rural Institute, Tamilnadu, India
*Corresponding Author E-mail: patric.tngtf@gmail.com
Online published on 6 March, 2013.
Corrosion rates of carbon steel immersed in various concentrations of Cl−(100 ppm and 150 ppm) have been evaluated by weight loss method in the absence and presence of Amino (trimethylene phosphonic acid) ATMP and Zn2+. It is found that ATMP alone is corrosive at 100 ppm Cl− but at 150 ppm Cl− it shows some inhibition efficiency (IE) due to deposition of Cl− on metal surface. However interestingly, ATMP shows very good IE in the presence of Zn2+ at all concentrations of Cl−. A synergistic effect is noticed between ATMP and Zn2+. The protective film has been analysed by surface analysis techniques and a suitable mechanism of corrosion inhibition is proposed.
Carbon steel, corrosion inhibition, chloride environment, phosphonic acid
