The rate of uniform corrosion, the likelihood of pitting and crevice corrosion for aluminum, Al, in white wine were investigated in this paper. In commercial wines, the K
2S
2O
5 is commonly added to induce free-SO
2 which reduces the dissolved oxygen and acts as a fungicide in the wine. The spontaneous electrode potential of Al,
ESP, in a deaerated wine containing less than 1ppm of free-SO
2, at 25°C was measured to be about -600mV vs. SCE. Since the K
2S
2O
5 is an oxidizing agent for the Al, the
ESP was ennobled with the addition of K
2S
2O
5 reaching -520mV with a concentration of 1000ppm K
2S
2O
5. The uniform corrosion rate was measured to be 13μm/y at 25°C and this rate was found to depend on the temperature with an activation energy of 42kJ/mol. However, this rate was found to have no dependency on the electrode potential within the
ESP range. The critical pitting potential,
VC, PIT, measured in the wine containing 25ppm of Cl
- was -370mV which was more noble than the
ESP, and the pitting corrosion can not occur. The repassivation potential for the growing crevice corrosion,
ER, CREV, was measured to be -530mV. It was also found that this potential does not depend on either the temperature or the concentration of K
2S
2O
5. It was observed that the
ESP became more noble than the
ER, CREV with the addition of 800ppm K
2S
2O
5 at 25°C. At a lower temperature, however, the
ESP became more noble than the
ER, CREV when a lesser amount of K
2S
2O
5 were added. An effective method to decrease the rate of uniform corrosion is to reduce the holding temperature; however, to effectively prevent the crevice corrosion at these lower temperatures, the K
2S
2O
5 concentration must be kept below 100ppm.
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