Pouteria sapota as green CO2-corrosion inhibition of carbon steel

Imidazoline obtained from the essential oil contained in Pouteria sapota seed was tested as an environmentally-friendly corrosion inhibitor of 1018 carbon steel CO2 saturated 3.5 % NaCl solution using electrochemical techniques. This imidazoline contains fatty acids with presence long hydrophobic chains, 52.73 unsaturated (oleic and linolenic acids) 40 (palmitic myristic compounds. Polarization curves revealed that this is highly efficient mixed-type efficiency 99.9 reached at 25 ppm. Also, lowest pitting potential value observed ppm inhibitor, making susceptible to type corrosion. Corrosion current density decreased by nearly four orders magnitude, a passive film formation induced for concen­tra­tions higher than 5 Accordingly, polarization resistance values were increased 100 W cm2 up about 106 inhibitor. The forms protective products adsorbed on metal surface very strong chemical way, following Langmuir adsorption isotherm. supported impedance spectra showed two relaxation processes ascribed electrode interface regions. In agre­ement data, total determined inter­facial charge transfer resistance, 8.2 ´ 105 SEM images additionally fully changed uniform localized when added into solution.