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stanfield
June 5th, 2002, 04:48 AM
What are all the distillation possible to produce nitric acid ? (with added sulfuric acid, huh !)
I know : - Sodium nitrate (the one I use !)
- Potassium nitrate
- Calcium nitrate if I remember correctly...
what's the suite ?

I posted this because I hope founding a cheaper nitrate than sodium nitrate !

thanx !

Synthetically Hopeful
June 5th, 2002, 05:09 AM
I seem to remember calcium nitrate being the best, but that was a long time ago, IIRC it dosent act as bad when adding it.

inferno
June 5th, 2002, 05:34 AM
A possible way of synthesising HNO<sub>3</sub>:

Chemicals needed
Sodium bisulphate (NaHSO<sub>4</sub>)
Nitrate ion source (KNO3, Ca(NO<sub>3</sub>)<sub>2</sub>, NaNO<sub>3</sub>, Ba(NO<sub>3</sub>)<sub>2</sub> etc)

Equipment needed (improvised, as not many people have good glassware)
Glass bottle/flask (wine bottle or something)
cork/stopper with hose or tube coming out
Acid-resistant container, with (salt) ice water in or around, if around it must have some water in it too
(Pyrex beakers are good, and, if youre at school, fit easily into your pocket)
Method
(I havent actually tried this, i only learnt of it in the last few days and have no nitrates atm nor sodium bisulphate. I read about it in an article about a 17 year old who made his own nuclear reactor, he used the acid to purify some uranium he obtained)

Put the sodium bisulphate and NO<sub>3</sub> donor in the bottle, flask or whatever youre using. Im not sure if you should put water in, but i think it *may* help. The container has to be heated, with an open flame (may crack though) or in an oil bath/hot water bath or something. A bunsen burner under a flask would work well. The gas resulting will go up through the tube, and the end of the tube must be secured into the ice bathed water. The gases escaping from the chemicals should condense in the cold water to make HNO<sub>3</sub>, though it will be very impure, and a purification method probably needs to be found, im sure theres a few, simple distillation might work.

I havent done this but im pretty sure it works. Anyway its a start for this board, arr so many new boards since yesterday!

da man
June 5th, 2002, 06:08 AM
Inferno, as some other members said, that reaction would happen at high temperatures, which would decompose the nitric acid into NO2, H2O, and O2.
Ammonium nitrate also works, 80g of ammonium nitrate + 90g of sulphuric acid works well. This was worked out by mongo blongo, so all credit goes to him :) This methods good for me, because i get my ammonium nitrate for $1.50 a Kilo!

stanfield
June 5th, 2002, 06:11 AM
Many people said to me that ammonium nitrate method doesn't work !?

rikkitikkitavi
June 5th, 2002, 06:19 AM
If you want to make HNO3 from H2SO4 (or NaHSO4) and Ca(NO3)2 you will have to make the Ca(NO3)2 in a solution, otherwise the solid gets coated with insoluble CaSO4, preventing further reaction.

Eventually, some CaSO4 dissolves and lets the underneath Ca(NO3)2 react but this is a much slower reaction.
(parallell to Na2CO3(aq) + Ca(OH)2(s) => CaCO3(s) + 2 NaOH (aq) , a very old way of making lye from boiling soda and lime together for many hours, and eventually the reaction completes )

I used a aprox. 4 M solution of Ca(NO3)2 and added eqimolar amount of
sulfuric acid. Cooling and ventilation!
Any higher concentration of Ca(NO3)2 and I found that the precitpated
CaSO4 made the whole into a sludge that wouldnt settle. But this is probably depending upon how fast you mix them. A slower mixing time gives larger CaSO4 crystals and easier settling time, because of lower oversaturation of CaSO4 in solution.

Anyway , after finishing the reaction, I let the CaSO4 settle and decanted of the top liqiud (8 M HNO3)- This I distilled until I got
aezotropic HNO3.

Unfortunately I only had access to non-vaccum proof glasware during this, but later I made > 68 % acid with NaNO3 and H2SO4.

/rickard

stanfield
June 5th, 2002, 06:34 AM
calcium nitrate in insoluble in sulfuric ? damn...
Even by heating the mix ? I hate the idea of adding water !

da man
June 5th, 2002, 06:41 AM
Stanfield, who said thet the Ammonium nitrate method didn't work, it worked for me (the distilling didn't work, but i know it made nitric, from the fumes, and i used it to make PETN, even without distilling it)?

inferno
June 5th, 2002, 06:54 AM
Da man - H2O+NO2 would reform to HNO3 (might need some compression though):

2H2O + 2NO2 ==> 2HNO3

And the gases would be going into a salt ice cooled container.

Mr Cool
June 5th, 2002, 08:27 AM
Inferno: not without oxygen it won't, check your equation...
It should be:
H2O + 2 NO2 + 1/2 O2 --> 2 HNO3

Flake2m
June 5th, 2002, 08:42 AM
I read in the book "Nitrogen and Phosphorus" a way to synthesise NO2, by adding an extra step to this process you could easily turn this into HNO3.

I dont have the book on hand, (I will have to borrow it from the libary) but I can remember the process invloved. A glass U tube in an ice bath connected to a test tube at one end. The test tube contained a small amount of Lead Nitrate (Pb(NO3)2) which was used in the demonstration. The other end of the U tube had a glass pipe that went into a beaker full of water. The beaker also contained a test tube full of water, that would displace some of the water in order to collect the NO2.

The PB(NO3)2 was heated at one end, as it decomposed into PbO it released NO2 gas. The NO2 gas then travelled into the U where the Ice bath could condense some impurities like N2O5. NO2 was then collected in the Test tube at the other end.

This method could work quite well if you have the equipment needed for this process.
This post will be edited when I have the book

rikkitikkitavi
June 5th, 2002, 09:18 AM
Ca(NO3)2 isnt insoluble in H2SO4, but CaSO4 is formed on the surface of the Ca(NO3)2 crystals, preventing a further reaction.

that said, solubility of CaSO4 is larger in H2SO4 than water due to
CaSO4 + H+ = Ca2+ + HSO4- but not much.

/rickard

stanfield
June 5th, 2002, 11:30 AM
The equation I use to distill is :
3NaNO3 + 2H2SO4-->3HNO3 + NaSO4 + NaHSO4
So, If I use Calcium nitrate, is this equation different ?

DBSP
June 5th, 2002, 01:49 PM
I belive you rection is wrong.

NaNO3 + H2SO4----> HNO3 + NaHSO4. You can't get more than one mole of HNO3 from 1 mole of H2SO4 since the second release of the H+ is performed at such high temperatures that the HNO3 formed would emmediately be decomposed.

mongo blongo
June 5th, 2002, 03:01 PM
Yes DBSP is right and I think it should be the same for Calcium Nitrate but I would stick to NaNO3.

rikkitikkitavi
June 5th, 2002, 04:07 PM
Ca(NO3)2 available as a fertilizer is many times a double salt:

Ca5(NH4)(NO3)11*10H2O Nitrogen content 15,6 %

Pure Ca(NO32) is usually available as Ca(NO3)2*4H2O
Nitrogen content 11,8 %
so you can separate them by reading at the package.

you have to dry it before making any HNO3 if you want to make high-conc. Dried CaNO3 is very very hygroscopic, like NH4NO3
Even if the NH4NO4 doesnt interfer I removed with GENTLY heating to
180-190 C (tried small batches at first) when the NH4NO3 decomposes into laughing gas:
NH4NO3 = N2O + 2 H2O
(technical method of making laughing gas)

Anyway, I never succeded making HNO3 from solid Ca(NO3)2 and H2SO4, some HNO3 was formed (heavy ,irritating white smoke) but later I realized that I probably have to crush or grind the salt into a extremely fine powder to increase reaction surface, which I didnt-

In solution it worked much better :)

/rickard

stanfield
June 5th, 2002, 04:22 PM
so, I must make a saturated solution of calcium nitrate then add sulfuric then distill... ok, but what about the concentration of final nitric acid ?

rikkitikkitavi
June 5th, 2002, 05:23 PM
check my other posts at the toppic : HNO3 from NaHSO4 and NaNO3...

/rickard

cspotdie
June 11th, 2002, 07:22 PM
Is the Sulfuric Acid used in Drain opener strong enough to use in the production of HNO3 ?

thanks

Lifes a bitch then you pay

photonic
June 11th, 2002, 08:00 PM
Sort of. It's diluted most of the time but you can just boil it to purify it. Boil it until you see white fumes and then you should have somewhere around 98% sulphuric IIRC.

megalomania
June 12th, 2002, 01:07 AM
The concentration sold for drain opening use varies, but it is typicially in excess of 96%. You will not have any luck just boiling it to get fumes, that trick is for battery acid. At this concentration it is quite useful in distilling nitric acid, up to about 96%. After you have used the sulfuric acid, it will contain water (the more water in the nitric the more the sulfuric will have), so you may then try the boil.

<small>[ June 12, 2002, 12:10 AM: Message edited by: megalomania ]</small>

Sparky
June 23rd, 2002, 11:28 AM
This is a bit off topic but: Can you use molecular sieves to dry nitric acid? I can assume you can't because nobody seems to but why not?

Sparky
June 25th, 2002, 08:33 PM
I was reading rec.pyrotechnics and I found a post that was dealing with nitrating cellulose.
<a href="http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&threadm=AtIQ8.52922%24s82.4103635%40news1.calgary. shaw.ca&rnum=1&prev=/groups%3Fq%3Dnitration%2Bof%2Bcommon%2Bce" target="_blank">http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF8&safe=off&threadm=AtIQ8.52922%24s82.4103635%40news1.calgary. shaw.ca&rnum=1&prev=/groups%3Fq%3Dnitration%2Bof%2Bcommon%2Bce</a> llulose%2Bgroup:rec.pyrotechnics%26hl%3Den%26lr%3D %26ie%3DUTF-8%26oe%3DUTF8%26safe%3Doff%26selm%3DAtIQ8.52922%25 24s82.4103635%2540news1.calgary.shaw.ca%26rnum%3D1

It states that magnesium nitrate can be used to concentrate nitric acid. Does anyone know a procedure for this? If you have say 50% nitric acid can you add magnesium, forming magnesium nitrate and drying the acid? What kind of concentration can be reached?

vulture
July 5th, 2002, 05:03 PM
I assume you can better use MgSO4 for this, which is a strong dessicant. It is freely available as epsom salt in the form of it's heptahydrate, MgSO4.7H2O. You just need to heat that till all the water comes off.
It won't react with the nitric acid because that would require the formation of H2SO4, which is a much stronger and less volatile acid, so that won't happen.