I have used the search engine and searched on sciencemadness but i didnt find any reliable source how to concentrate 40%nitric acid to 70%or higherAndersHoveland - 10-2-2012 at 23:26
You can add concentrated sulfuric acid (90-98%) to absorb the water, then extract the nitric acid from the concentrated acid mixture using methylene
chloride. Methylene chloride is commonly found in solvents available in automotive stores.UnintentionalChaos - 10-2-2012 at 23:44
You can add concentrated sulfuric acid (90-98%) to absorb the water, then extract the nitric acid from the concentrated acid mixture using methylene
chloride. Methylene chloride is commonly found in solvents available in automotive stores.
Your title is as relevant as ever.
Put a fractionating column (for best results, though simple distillation will work as well) and distill until the stillhead reaches 120C, the boiling
point of the ~69% nitric acid azeotrope. The distillate should be almost entirely water with traces of acid (significantly more acid will be wasted
this way without the column). The liquid in the stillpot is the more concentrated acid.
As a PS, nitric acid attacks the rubber typically used for thermometer adapters...I have one with a fluoroelastomer gasket that is fine. An IR
thermometer might be able to hazard a decent guess.weiming1998 - 11-2-2012 at 00:48
I have used the search engine and searched on sciencemadness but i didnt find any reliable source how to concentrate 40%nitric acid to 70%or higher
You have two options:
1, Distil the acid to its azeotrope
2, Neutralize the acid with a suitable base, evaporate the water, then add concentrated sulfuric acid. If you want 70% acid only, you can add 30 ml of
water per 70 ml of acid.Pulverulescent - 11-2-2012 at 01:04
Quote:
Your title is as relevant as ever.
There's a whole lot of shakin' going' on, but it's taking hours and hours to get nofuckingwhere!
My arms are aching at just the thought of it . . .
Quote:
I have one with a fluoroelastomer gasket that is fine.
Yeah! They're great ─ but sooo fucking losable ─ then it's back to the reliable old teflon tape . . .
Always keep a roll or twenty handy!
PPulverulescent - 11-2-2012 at 01:23
Quote:
Neutralize the acid with a suitable base, evaporate the water, then add concentrated sulfuric acid. If you want 70% acid only, you can add 30 ml of
water per 70 ml of acid.
You don't need the nitrate salt!
40% HNO<sub>3</sub> can be brought to >90% by distilling from 150% its volume of H<sub>2</sub>SO<sub>4</sub>!
The sulphuric acid can then be reconcentrated by heating in a well ventilated area, a fume-cupboard or downwind of the vapours!
Neutralize the acid with a suitable base, evaporate the water, then add concentrated sulfuric acid. If you want 70% acid only, you can add 30 ml of
water per 70 ml of acid.
You don't need the nitrate salt!
40% HNO<sub>3</sub> can be brought to >90% by distilling from 150% its volume of H<sub>2</sub>SO<sub>4</sub>!
The sulphuric acid can then be reconcentrated by heating in a well ventilated area, a fume-cupboard or downwind of the vapours!
P
I assume that this works by bringing the boiling point of water to 300 degrees celsius, so that the nitric acid easily boils away? But what about the
azeotrope of nitric acid with water? The attraction between sulfuric acid and water can break an azeotrope? Or sulfuric acid disrupts the azeotrope?Vikascoder - 11-2-2012 at 01:56
Why not to freeze than take ice out and save nitric acid why always boils and my distilling kit was attacked by nitric acid as someparts were made up
of rubber . So any other way rather distilling Vikascoder - 11-2-2012 at 01:57
Why not to freeze than take ice out and save nitric acid why always boils and my distilling kit was attacked by nitric acid as someparts were made up
of rubber . So any other way rather distilling Pulverulescent - 11-2-2012 at 01:58
In the distillation, strong nitric acid comes over from the soln when the temperature is held @ 120°C.
The sulphuric acid binds up the water at this temperature . . .
P hkparker - 11-2-2012 at 02:14
The methylene chloride "extraction" method was passed around on a drug forum a while ago, the actual entire procedure was extremely frightening.
Someone on youtube send it to me asking if it was ok...
Distilling out the water with a fractionating column like UnintentioalChoas said is the best method. For concentrations >70% sulfuric acid does a
good job of breaking the azeotrope, and lets you distill RFNA. Vacuum distillation at lower temperatures will produce WFNA.weiming1998 - 11-2-2012 at 15:21
Why not to freeze than take ice out and save nitric acid why always boils and my distilling kit was attacked by nitric acid as someparts were made up
of rubber . So any other way rather distilling
Because homogeneous mixtures are very difficult to separate by freezing! If you put the 40% nitric acid in a freezer, the water wouldn't freeze, even
if it is below 0 degrees celsius. If you get a low enough temperature, then all of the acid will freeze. UnintentionalChaos - 11-2-2012 at 17:42
There's a whole lot of shakin' going' on, but it's taking hours and hours to get nofuckingwhere!
My arms are aching at just the thought of it . . .
Quote:
I have one with a fluoroelastomer gasket that is fine.
Yeah! They're great ─ but sooo fucking losable ─ then it's back to the reliable old teflon tape . . .
Always keep a roll or twenty handy!
P
You can buy the fluoroelastomer o-rings for 15 cents each if you look in the right places. they tend to get trashed after use with halogenated organic
solvents anyway and should be replaced every once in a while.Vikascoder - 12-2-2012 at 04:51
I am thinking if calcium nitrate is mixed with sulfuric 98% acid will it make nitric acid above 70 %solution and calcium sulphate which can be
filtered and then i will not need to distill the solution just . Tell me i will need to distill or nitric acid will be formed in liquid form in that
beaker. Of high concentrationvulture - 12-2-2012 at 05:44
Quote:
The methylene chloride "extraction" method was passed around on a drug forum a while ago, the actual entire procedure was extremely frightening.
Someone on youtube send it to me asking if it was ok...
I performed this method, it's not frightening, it works rather well and it has been described on this forum. Certainly safer than vacuum distillation.Pulverulescent - 12-2-2012 at 05:51
Tell us more, vulture?
I'd heard it was a lot of work for little reward ─ I'm still interested, though!
Phkparker - 12-2-2012 at 14:04
Please do tell, I too have heard very negative things but I'd be curious to see the results you got.
