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Is "alumina content" different than "dissolved aluminum"?

Hello my name is Peter Totaro. I am a chemist at an anodizing shop in Paterson New Jersey. I have been doing the sulfuric acid anodizing method for finding dissolved aluminum and getting an answer that is the same as alumina for my ps 13201 spec for boeing. Now is dissolved aluminum and alumina the same thing or different? I'm interested to know and, if they aren't, do you know of a method for alumina? thank you very much.

Peter Totaro
chemist - Paterson
April 27, 2011

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Alumina usually refers to Al2O3, so you'd need to make a conversion. In any case, the titration analysis for alumina is included in PS13201, so why not use their published method which would be accepted by your auditors?

Jon Barrows, MSF, EHSSC
GOAD Company

Independence, Missouri

First of two simultaneous responses -- April 27, 2011

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I am not acquainted with your spec, but suffice it to say that alumina is the common name for aluminium oxide (Al2O3) and dissolved aluminium is exactly what it says - aluminium ions in solution, where it will exist as Al(3+).

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
Second of two simultaneous responses -- April 28, 2011