Cecil says that the reason that ketchup dissolves aluminum foil is that ketchup is acidic (3.85). Then he says that Coke is even more acidic at 2.7. But Coke is packaged in an aluminum container! Why doesn’t the can melt?
Soda cans are lined.
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Why does ketchup dissolve aluminum foil? (25-Jun-1982)
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A short description of How Cans Are Made.
Believe it or not, the Master has written about this very issue:
I was just about to say that!
Thanks. I can’t usually get the dope’s search engine to work for me, so appreciate the info. It’s something I’ve often wondered about. Interestingly, the link to the canmaker’s web page in the UK said the coating was a lacquer, and Cecil mentioned a “light plastic” compound. I’m not sure if the definition of lacquer can include plastics or not, and the two sites are from different countries, (so I’m not saying Cecil is wrong), but I think I’m going to do a little more research webwise on what the actual coating is, what kind of plastic or whatever. I guess I’ll post it here if I find anything.
This from here: http://es.epa.gov/techinfo/research/reduce/rrel508.html
Liquid hazardous wastes are generated from the painting and inking operations in the form of excess paint and ink cleaned from machinery. Most of the paint wastes are from the water- based paint used to coat the inner can surfaces. Although the paints and inks are water-based, they contain ethylene glycol monobutyl ether, n-butyl alcohol, dimethylethanolamine, and 2-butoxyethanol; the paint wastes are considered hazardous and are shipped to a hazardous waste disposal facility.