Aquilaria Crassna Leaves Extracts - a Green Corrosion Inhibitor for Mild Steel in 1 M HCl Medium

作者：Helen L Y S; Rahim A A^*; Saad B; Saleh M I; Raja P Bothi

来源：International Journal of Electrochemical Science, 2014, 9(2): 830-846.

• adsorption isotherm
• agarwood
• Aquilaria crassna
• corrosion inhibition

The anti corrosion behaviour of agarwood leaves extracts in 1 M HCl solution on mild steel were studied using gravimetric method (weight loss method), electrochemical methods (electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation) and scanning electron microscope (SEM) techniques. The extracts were shown to have good inhibition efficiencies for the gravimetric and electrochemical methods. EIS analysis revealed that increase in concentration increases the charge transfer resistance, thus increased inhibition efficiency. The potentiodynamic polarisation measurements showed the extracts acted as mixed-type inhibitors with predominantly cathodic effectiveness. SEM techniques supported the success of corrosion inhibition with the presence of inhibitors and the methanol extract best fitted the Temkin adsorption isotherm while the aqueous extract best fitted the Langmuir and Temkin adsorption isotherms. The adsorption mechanisms for both extracts were mainly physisorption.

• 出版日期2014-2