John paul III
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Synthesis of calcium metal from compounds by use of potassium
I came across an easy way to get K metal from K2O. I'd like to use it to get calcium metal from CaO, Ca(OH)2 or CaCO3. Can it be done (practically)?
[Edited on 28-4-2018 by John paul III]
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aga
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Starve.
Edit:
A new tactic. If it's complete rubbish, just say 'starve'.
Hopefully people will not reply to utter garbage thereafter.
[Edited on 28-4-2018 by aga]
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Metacelsus
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Can it be done? In theory Ca can be made by reacting K with CaO, since the reduction potential of K+ is more negative than that of
Ca2+. However, I don't think it's very practical to actually do the reaction.
Industrially, Ca is produced from CaO by reaction with Al at >1200 °C, see: http://jes.ecsdl.org/content/89/1/207
[Edited on 4-28-2018 by Metacelsus]
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Texium
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Quote: Originally posted by aga  | Starve.
Edit:
A new tactic. If it's complete rubbish, just say 'starve'.
Hopefully people will not reply to utter garbage thereafter |
How about not, unless you want a temporary ban
for a couple weeks? Post "starve" one more time and that's exactly what you'll get. This isn't funny.
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Texium
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Thread Moved
28-4-2018 at 14:56 |
j_sum1
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Well, at a quick glance the thermodynamics is not unfavourable.
K2O heat of formation = -363 kJ/mol
CaO heat of formation = - 635 kJ/mol
The next step would be to do some research on designs of similar reactions. I suspect you will have very significant problems with your potassium
boiling away. Now it might be kind of interesting to see a hot green metallic gas eminating from your apperatus. But only enjoyable from a
considerable distance.
@ aga. Not a good tactic. Don't do this again. You have far more intelligence, knowledge and humour than this and don't need to be so dismissive. If
the question bores you or you have nothing to contribute then don't respond. If everyone agrees with you the thread will sink like a stone.
Edit: ninja'd by Texium.
[Edited on 28-4-2018 by j_sum1]
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LearnedAmateur
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I’d also be keeping that potassium and figuring out other routes to obtain calcium metal, but I’ve already got a few grams of the latter for
whenever I may need it during the course of experimentation. Personally, I’d go with electrolysis of a molten calcium salt under inert atmosphere if
I were ever to attempt to isolate the element. But, if you’ve got loads of potassium to spare then who am I to dissuade you; it’s more reactive
than calcium so you can utilise it as an extraction reagent through some processes.
In chemistry, sometimes the solution is the problem.
It’s been a while, but I’m not dead! Updated 7/1/2020. Shout out to Aga, we got along well.
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John paul III
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| Quote: Originally posted by aga | Starve.
Edit:
A new tactic. If it's complete rubbish, just say 'starve'.
Hopefully people will not reply to utter garbage thereafter.
[Edited on 28-4-2018 by aga] |
I remind you that calcium can be used to fix nitrogen (calcium nitride), provided that you have an oxygen separator. Ideally I'd add drops of water to
it collecting ammonia, and then recycle the calcium
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John paul III
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| Quote: Originally posted by Metacelsus | Can it be done? In theory Ca can be made by reacting K with CaO, since the reduction potential of K+ is more negative than that of
Ca2+. However, I don't think it's very practical to actually do the reaction.
Industrially, Ca is produced from CaO by reaction with Al at >1200 °C, see: http://jes.ecsdl.org/content/89/1/207
[Edited on 4-28-2018 by Metacelsus] |
Since potassium has a low melting point it should be easier to ignite the mix with CaO, right? (I realise that 1200C for the Al fueled thermite is way
above melting point of aluminium) Potassium is sometimes used to ignite aluminium thermite
Beware, this paragraph will contain exotic ideas:
Now, the problem would be potassium boiling. I thought of reacting tiny quantities, in a kind of a "borehole" to contain the explosion products
without producing shrapnel. Do you think the reaction could be fast enough?
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