الفهرس | Only 14 pages are availabe for public view |
Abstract The present work is assigned to study the corrosion behavior of carbon steel in 0.5 M H2SO4 and the inhibiting effect of some plant extracts. The obtained results from weight loss method showed that the inhibition efficiency of these extracts increased by increasing their concentration and increase with increasing temperature for (Ficus carica, Plantago major) extracts so that the adsorption of these extracts is chemical but for (Solenostemma argel) extract the inhibition efficiency decreased by increasing the temperature so the adsorption of this extract is physical. The adsorption of plant extracts (Ficus carica, Plantago major) on carbon steel surface in 0.5 M H2SO4 follows Temkin isotherm but (Solenostemma argel) extract follow Langmuir isotherm. Some thermodynamic parameters are computed and discussed. The polarization curves indicated that these extracts influence both cathodic and anodic processes to the same extent. from the impedance spectroscopy data, we conclude that: The value of Rct increases with increasing the concentration of the plant extract inhibitors. from the Electrochemical frequency modulation data, we conclude that the corrosion current density decreases by increasing the concentration of the studied plant extracts. The surface morphology of carbon steel was studied by AFM. The results obtained from different techniques were in good agreement. |