Corrosion Behavior of 3104 Aluminum Cans When Used as Packaging for Chinese Liquor

Aluminum cans are commonly used for packaging soft drinks and low-alcohol beverages due to their good recyclability. To enhance the economic cycle and expand the packaging of liquors, the feasibility of commercial 3104 aluminum cans for packaging Chinese liquor was studied. The aluminum's migration into alcoholic solutions was studied using inductively coupled plasma emission spectroscopy (ICP-OES). Electrochemical impedance spectroscopy (EIS) was used to study the corrosion process of epoxy coatings on the aluminum cans. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), infrared attenuated total reflection (IR-ATR), and X-ray diffraction (XRD) were used to determine the inner coatings and adhering surfaces of the cans and the corrosion process. The results showed that the maximum aluminum migration in Chinese liquor was 4.3572 mg/kg at 60 °C for 30 days. The epoxy coating was corroded enough to decrease the coating impedance and expose the metal substrate after 25 days. Permeation and aging degradation of coatings are the main factors to consider when packaging liquor.