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Author Topic: Can barium chloride (BaCl2) be made from barium sulphate (BaSO4)?  (Read 4291 times)

Offline Bill.D.Katt.

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I've been wondering how I could make BaCl2 from BaSO4. Wikipedia states: "BaSO4 + 4 C → BaS + 4 CO" then "BaS + CaCl2 → BaCl2 + CaS" (http://en.wikipedia.org/wiki/Barium_chloride) It states that this is performed on an industrial scale, could this be done on a minor scale, and are there any other methods?
« Last Edit: 27/04/2011 08:10:53 by chris »


 

Offline lightarrow

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BaSO4 + 2Al --activation energy--> Al2O3 + BaO + S

or, maybe:

3BaSO4 + 8Al --activation energy--> 3Al2O3 + 3BaO + Al2S3.

Then you dissolve BaO with HCl. Al2O3 doesn't dissolve in it, Al2S3 forms, I think, AlCl3 (soluble) and H2S (very poisonous).

To favour the first reaction, I would use an excess of BaSO4 with respect to Al. Furthermore, the reagents should be in powders mixed extremely well.
« Last Edit: 25/04/2011 12:48:23 by lightarrow »
 

Offline Bill.D.Katt.

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Oh, wow. That was an energetic reaction. Not as bright as thermite, but hot enough to burn through the steel pan it was on. So I just throw the powdery stuff left over into some HCl? Once it has fully reacted to AlCl3 and BaCl2 do I force it out of solution by fractional crystallization (after evaporating off excess HCl)? Or can I through a base into solution and only precipitate out one species?
 

Offline lightarrow

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Oh, wow. That was an energetic reaction. Not as bright as thermite, but hot enough to burn through the steel pan it was on.
I hope you used an excess of sulphate as I said, otherwise I think it is, as or more bright than thermite...

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So I just throw the powdery stuff left over into some HCl?
Yes, you should first disgregate it in powder if it's in greater pieces. Then I would use diluted HCl (it's enough to react with BaO and it's not enough to react with Al2O3).

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Once it has fully reacted to AlCl3 and BaCl2 do I force it out of solution by fractional crystallization (after evaporating off excess HCl)? Or can I through a base into solution and only precipitate out one species?
Better the second: Al(OH)3 precipitates just from pH > 4. At pH = 6 is completely precipitated. You can increase pH up to 9; for pH > 9 the Al(OH)3 begins to dissolve as alluminate, so I would adjust the pH to ~ 7. Ba(OH)2 is soluble so you don't have the problem of this precipitate.
 

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