History of Lithium: Isolation

[battousai]

I originally looked on wikipedia for the history of lithium, and how it was first isolated. It says, "William Thomas Brande performed electrolysis on lithium oxide", but without any specifics, as in chemical equations, voltage potentials, apparatus, and if the salt was molten or not. Now, the reason I am interested, is because I *think, that William Thomas Brande isolated lithium by dissolving lithium oxide in a polar aprotic solvent; thus allowing electrolysis without fusing the lithium oxide.

 

Anyway, back to the point, I cannot seem to find the specific's for Brande's process anywhere. On the internet, I only find the same sentence repeated on many websites, and I even checked my municipal library, but sadly, they do not have any books that seem to be relevant to my question, nor any books on William Thomas Brande himself.

 

Does anyone know of a reliable source that does state the specifics of Brande's process?

[jrayj]

In the same wikipedia article under production I found "The metal is produced electrolytically from a mixture of fused lithium and potassium chloride. In 1998 it was about US$ 43 per pound" I would assume that if it was possible to produce it using a solvent instead it would be more eficient and would be the main commercial process used. No info on Brande's process though.

[UC]

If you follow the link in the lithium article to the Sir Humphrey Davy article, you will find that Lithium oxide is almost surely a typo and should be lithium hydroxide. Electrolysis of molten lithium hydroxide generates the molten metal at the cathode

Edited January 11, 2009 by UC

[battousai]

I don't think it is a typo. After further search on google, I have found the book in which wikipedia sourcesseen here, and on page 125, it says, "Brandes finally succeded in decomposing lithia with a powerful battery...". Then from wikipedia again, you can see that lithia means lithium oxide. Still, the book has no mention on the process used... I've yet to research the sources given by this book, perhaps they will explain.

In any case, the book also states, "Davy also obtained a small amount of lithium in the same manner", and since we know Davy fused his salts, it is likely that the book means Brandes also fused lithia to perform electrolysis. However, I am determined to find out what really happened.

[UC]

Keep in mind that Li2O is an extremely hygroscopic, stripping water from the air to make Lithium hydroxide. Lithium oxide also has a very, very high melting point, above the boiling point of lithium. I suspect that he wouldn't have collected much metal if it was being evolved as a gas that would ignite on exposure to air. Also, it may well be that lithium oxide is soluble in molten lithium hydroxide and what they thought was the oxide was a mixture of the two. Lithium hydroxide has a sufficiently low melting point for Lithium to be formed as a liquid.