virgilius1979
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Concentrating acids with P4O10
I know P4O10 can be used for dehydrating sulfuric or nitric acid, but I don't know if these concentrated acids can be used directly or they need to be
distilled.
Supposedly we want to get sulfuric oleum: how should we proceed in order to get rid of H3PO4 resulted from P4O10 and water in H2SO4, because I think
SO3 would come out first, but than it would be followed by H3PO4, and only at the and would come pure H2SO4. Am I right ? Did anyone tried this ?
What about getting N2O5 from nitric acid using P4O10 ?
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bbartlog
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| Quote: | | I think SO3 would come out first, but than it would be followed by H3PO4, and only at the and would come pure H2SO4. Am I right ?
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No.
The less you bet, the more you lose when you win.
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12AX7
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Namely, H3PO4 is not volatile; at worst it dehydrates to polymeric HPO3 or something like that. Not that H2SO4 and company are particularly volatile
themselves.
Tim
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woelen
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You need a lot of P4O10 to get a small quantity of SO3. I tried this myself and I found it to be a very non-economic route to SO3.
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virgilius1979
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Quote: "Namely, H3PO4 is not volatile; at worst it dehydrates to polymeric HPO3 or something like that. Not that H2SO4 and company are particularly
volatile themselves."
Bbartlog, I meant if I want to distill the whole mix which comes out first, I know these acids are not volatile by themselves.
Thanks woelen. I read the SO3 thread, and I'll try with Na/K persulfates or bisulfates if I want some SO3.
I was also interested if the phosphoric acid present could interfere with HNO3 in a nitration reaction, like in RDX synthesis, which I know is a bit
more difficult than other nitrations.
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