Gallic Acid as a Potential Green Corrosion Inhibitor for Aluminum in Acidic Solution

Metals

Agnieszka Podborska¹  Kamil Dychtoń²  Barbara Kościelniak²  Przemysław Kwolek²  Andrzej Obłój²  Marek Wojnicki³ 

[1] Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Mickiewicza Avenue 30, 30-059 Krakow, Poland;Department of Materials Science, Faculty of Mechanical Engineering and Aeronautics, Rzeszow University of Technology, Żwirki i Wigury Street 4, 35-036 Rzeszow, Poland;Faculty of Non-Ferrous Metals, AGH University of Science and Technology, Mickiewicza Avenue 30, 30-059 Krakow, Poland;

关键词: gallic acid;    aluminum;    corrosion inhibition;    orthophosphoric acid;    green corrosion inhibitor;   

DOI  :  10.3390/met12020250

来源: DOAJ

【 摘 要 】

Plant extracts are intensively studied as green corrosion inhibitors of aluminum. Because these extracts are complex systems, the influence of their individual constituents on the corrosion of aluminum should be determined. In this work, gallic acid was tested for the first time as a corrosion inhibitor of aluminum in orthophosphoric acid aqueous solution. So far, its potential inhibiting properties in acidic solutions were only suggested based on promising results obtained for various plant extracts. Evaluation of the potential inhibiting properties of gallic acid was performed using electrochemical methods. The corrosion potential, polarization curves, and impedance spectra of aluminum in 0.5 M orthophosphoric acid, at T = 303 K, were determined. The corrosion potential, corrosion current density, and corrosion rate of aluminum in orthophosphoric acid were equal to −1.151 V vs. Ag|AgCl (3M KCl) reference electrode, 36 μA∙cm⁻² and 0.39 mm∙year⁻¹, respectively. These values did not change with the addition of gallic acid. The results obtained show that gallic acid does not inhibit aluminum corrosion. UV-Vis absorption spectra of gallic acid solutions and quantum mechanical calculations show that this organic compound did not adsorb onto the aluminum surface under the studied conditions.

【 授权许可】

Unknown