Assessment of the Bassia muricata extract as a green corrosion inhibitor for aluminum in acidic solution

The inhibiting behavior of aluminum by the Bassia muricata extract was examined in 1.0 M H2SO4 solution as a green corrosion inhibitor via weight loss, potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. It was found that the addition of the extract reduces the corrosion rate of aluminum alloy. The inhibition efficiency increases with increasing extract concentration and reached 90% at 300 ppm. The inhibitive effect of the tested extract was discussed in view of adsorption of its components on the aluminum surface. The effect of the temperature on the corrosion behavior with the addition of different concentration of B. muricata extract was studied in the temperature range of 298 and 318 K. The B. muricata extract adsorption isotherm on the aluminum surface was followed the Temkin adsorption model. The activation and adsorption parameters were computed and discussed. Tafel plots showed that the B. muricata extract represented as a mixed type inhibitor. The surface morphology was examined via scanning electron microscopy (SEM) and atomic force microscopy (AFM) which confirmed the existence of a protective film of inhibitor molecule on the aluminum surface. The results revealed that the B. muricata extract was an effective inhibitor, and the inhibition efficiencies gained from all applied techniques were in good agreement. [GRAPHICS] .