A novel Tri-cationic surfactant was prepared by the reaction of cetyl-2-chloroacetate with di amide. The chemical
structure of the prepared compound was confirmed by FTIR and 1HNMR. The critical micelle concentration value of the
prepared surfactant was determined by surface tension and conductivity measurements. The prepared compound was
examined as corrosion inhibitor for carbon steel in hydrochloric acid solutions using weight loss and potentiodynamic
polarization methods. Tafel polarization studies showed that the surfactant is mixed type inhibitor. The adsorption of the
prepared compound on to the surface of carbon steel in 1 M HCl obeys the Langmuir isotherm. Also, activation
thermodynamic parameters such as Ea, ∆H* and ∆S* were calculated using Arrhenius and transition state equations and
discussed.