Sciencemadness Discussion Board

Nitric acid distillation goes wrong.looking for alternatives.

bold_ing - 15-4-2019 at 13:14

...So this is my first post so excuse any mistakes.
I like nitrogen.I like nitrogen compounds even more.I love nitric acid.
so during the past month i was able to get my hands on some potassium nirate finally and i wanted to make nitric acid, nut being just a chemistry enthusisat with a low budget i couldn't get any proper lab equipment.
most suppliers would only sel in large orders or to professional labs.
so i started looking for a way to make a nitric acid distillation apparatus with common stuff i couldget at the hardware store.
i've gotten myself some epoxy,PEX tubing,some glass bottles and i made a retort like system that could function as a distillation set up for nitric acid.
i used 30%sulfuric acid KNO3 put the "ptfe coated" lid on the glass bottle ,put it in a sand bath and turned on the heating.
15mins later everything was going great.
25mins later the mixture starts boiling and the first few drops were collecting (pretty dilute hno3)
the way i made that set up is by drilling a hole into a teflon coated metal lid and inserting the PEX tubing in holding it with some epoxy and bending teh tube as to lead down teh vapors/condensate down into to chilled collection container.
40mins later the pex tubing and the epoxy inside the bottle start reacting and bubbling and reats to form this gooey mess that was dripping straight into the boiling acid mix, but it was still collecting pretty much clean acid and so i i decided to keep going (bad idea)
a few more miutes pass by and the non cooled condenser part of the tube starts to get really really hot and not much of the acid vapors condense
i no longer can see what's happening inside the bottle as it is FILLED with NO2.
i cut off the heat but it was too late as the mixture foamed over into the tube where it solidified and caused a pressure build up (containing hot azeotropic nitric acid and lots of no2 gas) eventually eating through the metal lid and shooting HEAPS of that no2 crap alll over the room which made me run for my life as i could no longer breath , after a couple of hours i checked the mess out and i found cracked glass all over the bench and anything metal was very badly corroded withing the room.
it was bad.
so all of this to ask yall guys to maybe suggest ANY other way that could be successfully used to distill nitric acid without buying lab glassware as i really don't have easy acess to it.
i know there isn't much that could withstant hot nitric acid vapors and it's not the smartest thing to do but oh well. thanks;)
apologies for lacking english and long post.

Loptr - 15-4-2019 at 13:45

Get an actual retort online. It isn't that expensive.

I wouldnt suggest rigging up anything to distill nitric acid. Its risky enough using regular glassware.

CharlieA - 15-4-2019 at 16:14

It is always best to confine ones self to experiments for which he has the proper needed chemicals and apparatus, and knows the proper techniques. I think you wait until you can afford a basic, borosilicate glass distillation apparatus, of which there are many available on ebay.

hissingnoise - 16-4-2019 at 06:29

Quote:
Get an actual retort online. It isn't that expensive.

I wouldnt suggest rigging up anything to distill nitric acid. Its risky enough using regular glassware.

Retorts are of little use for NA distillation as you can't really connect one to a condenser.

All the OP needs is flask, adapter and condenser with tapered joints ─ it'll hardly break the bank...

CouchHatter - 16-4-2019 at 18:07

NurdRage has a video with three very concise methods for preparing varying concentrations of nitric acid.

chemplayer... - 18-4-2019 at 00:50

No safe way to do it without ground glass equipment. Virtually all plastics, plasticisers, and metal components are going to react with the concentrated nitric acid vapour.

Alternative is to mix the sulfuric acid and nitrate salt, use DCM to extract the nitric acid, then separate the DCM and mix with water whereby the nitric acid will go into aqueous solution. This will give you an aqueous solution of nitric acid. Certainly can't recommend distilling off the DCM though as the mixture could be prone to being unstable and potentially explosive with high nitric acid concentrations.

MrHomeScientist - 18-4-2019 at 07:36

Second all the points about glass - you pretty much need ground glass to do this successfully. Nitric acid is just too corrosive to anything else (even rubber stoppers). But one flask, an adapter, and a condenser won't be very expensive online, as hissingnoise mentioned. eBay and Amazon are your friends.

Another thing to note is with only 30% sulfuric acid, you'll only get very dilute nitric acid since all that water will be coming over as well. I used 98% acid, bought at the hardware store as "liquid fire" drain cleaner.

bold_ing - 20-4-2019 at 08:10

Quote: Originally posted by CouchHatter  
NurdRage has a video with three very concise methods for preparing varying concentrations of nitric acid.



I watched that video but it really only produced very dilute and sometimes dilute and contaminated acid so...
my goal is the 68% azeotrope.

bold_ing - 20-4-2019 at 08:12

Quote: Originally posted by chemplayer...  
No safe way to do it without ground glass equipment. Virtually all plastics, plasticisers, and metal components are going to react with the concentrated nitric acid vapour.

Alternative is to mix the sulfuric acid and nitrate salt, use DCM to extract the nitric acid, then separate the DCM and mix with water whereby the nitric acid will go into aqueous solution. This will give you an aqueous solution of nitric acid. Certainly can't recommend distilling off the DCM though as the mixture could be prone to being unstable and potentially explosive with high nitric acid concentrations.

I have never heard of the DCM meathod which definitely seems interesting,maybe if concentration isn't taken into consideration

bold_ing - 20-4-2019 at 08:21

Quote: Originally posted by MrHomeScientist  
Second all the points about glass - you pretty much need ground glass to do this successfully. Nitric acid is just too corrosive to anything else (even rubber stoppers). But one flask, an adapter, and a condenser won't be very expensive online, as hissingnoise mentioned. eBay and Amazon are your friends.

Another thing to note is with only 30% sulfuric acid, you'll only get very dilute nitric acid since all that water will be coming over as well. I used 98% acid, bought at the hardware store as "liquid fire" drain cleaner.

yup.the concentrated drain cleaner...I looked but I couldn't find it anywhere lol , all that was available as a liquid type drain cleaner was a solution of NaOH.
I decided to use the 30% sulfuric acid to see what will happen cause if a failure is due to happen I would prefer to be dealing with less concentrated chemicals and it would reach an azeotropic mix anyways.
And that's where the trouble began.

I definitely learned a lesson , and I'll be getting proper equipment soon as I found a source that's willing to sell.

hissingnoise - 20-4-2019 at 09:34

Quote:
I have never heard of the DCM meathod which definitely seems interesting,maybe if concentration isn't taken into consideration

What the "DCM method" has going for it is that near-anhydrous WFNA can be extracted by using strong H2SO4...

bold_ing - 21-4-2019 at 09:52

Quote: Originally posted by hissingnoise  
Quote:
I have never heard of the DCM meathod which definitely seems interesting,maybe if concentration isn't taken into consideration

What the "DCM method" has going for it is that near-anhydrous WFNA can be extracted by using strong H2SO4...


how would you be able to do that ?
I thought that having to disolve the nitric acid in water would lower it's concentration

hissingnoise - 22-4-2019 at 06:29

Sometimes only the very strongest acid will do in organic nitration ─ but if you're diluting it, always add the acid to water to avoid overheating the solution.

Tellurium - 22-4-2019 at 09:27

Hey,
I can't help you with getting nitric, but I also don't have that much budget to spend and if you need cheap glassware with good quality I strongly suggest you to visit deschem on the US-Ebay site.
I got my 24/29 vacuum destillation kit there for under 30 Bucks back in time and it served me the last 3 or so years without problem. Also try to look for laboratory closure sales or private people selling used glassware. I got glassware with a value, when buying new, worth around 1000$ for just 80$ and it's branded glassware from VWR with lots of condensers and so on. I also did chemistry for many years without all of the expensive glassware, but trust me: it's a one time investment and it helps A LOT to make things much easier and also open completely new possibilities:)

[Edited on 22-4-2019 by Tellurium]