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Corrosion of "pure" aluminum

I understand that pure aluminum can be much more resistant to corrosion than can its alloys. Can chemically pure aluminum resist long term aqueous LiCl, 45% by weight, at 300F, with or without the presence of oxygen? (If pH is maintained below 7?) If so, what level of impurity can be tolerated (are there commercially available forms at reasonable cost)? Any information in this regard is deeply appreciated.

Tom Tonon
- Princeton Junction, NJ

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Sounds like a CO2 scrubber or a fuel cell problem to me. I really don't recommend the use of aluminium with such high levels of chloride. You get severe intergranular attack with deep pitting and perforation in a very short time. High silicon alloys tend to be more resistant. 'Absolutely pure' aluminium is expensive and soft. 'Pure' aluminium tends to contain copper / magnesium / zinc / silicon. They will tend to exacerbate the problem.

I recommend that you line the aluminium with polypropylene (PP) OR use a completely PP / PE substitute. Let me know how it goes.

John Tuohy
- Ireland