Corrosion Behavior of Aluminium-Coated Cans

Area of Science:

• Materials Science
• Corrosion Engineering
• Food Science

Background:

• Billions of aluminum cans are used globally for beverages.
• Concerns exist regarding aluminum leaching and bisphenol A (BPA) from can coatings.
• The corrosive potential of beverage solutions on aluminum cans requires investigation.

Purpose of the Study:

• To evaluate the performance and quality of aluminum cans from Green Cola and Red Bull.
• To assess the impact of beverage solutions and acetic acid on can corrosion.
• To analyze aluminum dissolution and material degradation under various conditions.

Main Methods:

• Electrochemical techniques: potentiodynamic polarization and impedance spectroscopy (EIS).
• Elemental analysis: Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Energy Dispersive X-ray Spectroscopy (EDS).
• Material characterization: Scanning Electron Microscopy (SEM) and X-ray Diffraction Spectroscopy (XRD).

Main Results:

• Internal can coatings offered some corrosion protection but did not prevent aluminum dissolution.
• Green Cola's solution exhibited extreme corrosivity, increasing corrosion rates by approximately 333% compared to acetic acid.
• Uncoated cans showed increased oxygen content, more corrosion spots, and reduced crystallinity.
• ICP-OES detected dangerous aluminum levels in Green Cola, escalating with solution conductivity.

Conclusions:

• Beverage solutions can induce significant aluminum corrosion and leaching from cans.
• Green Cola's formulation poses a higher corrosion risk to aluminum packaging.
• Material integrity and potential health risks associated with aluminum dissolution warrant further attention.