Inhibition of aluminum corrosion in hydrochloric acid solution using black mulberry extract.

Inhibition of Aluminum corrosion in 2M hydrochloric acid solution using black mulberry (Morus nigra L.) extract has been studied by weight loss, electrochemical polarization technique and hydrogen evolution measurement. It was found that the berry extract acts as a good inhibitor for aluminum corrosion in the acid solution. The inhibition action of the extract in was discussed in view of the adsorption of its components on aluminum surface. It was found also that the adsorption is a spontaneous process and follows Langmuir adsorption isotherm. The inhibition efficiency (IE) increases as the extract concentration is increased. More over, the effect of temperature on the IE was studied. The IE decreases with increased the temperature. It was found that the presence of extract increases the activation energy of the corrosion reaction. Moreover, the thermodynamic parameters of the adsorption process were calculated. It was found also that the extract provides a good protection to aluminum against pitting corrosion in chloride ion containing solutions