Sciencemadness Discussion Board

HNO3 Storage?

Camroc37 - 2-5-2016 at 12:56

I noticed my HNO3 had eaten my caps on my boston round bottles :/ what is the best way to store HNO3?

Loptr - 2-5-2016 at 13:05

Glass bottle with a ground glass stopper. Lightly greased. I also put wire around the stopper and bottle neck to keep it from blowing out due to pressure.

I find this to be the case for many obnoxious things.

[Edited on 2-5-2016 by Loptr]

a nitrogen rich explosive - 2-5-2016 at 13:15

If you have really strong stuff (anhydrous perchloric acid etc.) ask for someone to line it with Teflon.

Camroc37 - 2-5-2016 at 13:40

Quote: Originally posted by Loptr  
Glass bottle with a ground glass stopper. Lightly greased. I also put wire around the stopper and bottle neck to keep it from blowing out due to pressure.

I find this to be the case for many obnoxious things.

[Edited on 2-5-2016 by Loptr]

Thanks, I thought that might work. Guess I'll have to do without a receiver flask for now.

XeonTheMGPony - 2-5-2016 at 14:41

proper way is in an all glass amber bottle in a fridge or freezer, I store most my chemicals in the freezer set to the highest temp it will go so -10 or so.

I wrap the glass stopper with Teflon tape rather then grease as well.

Camroc37 - 2-5-2016 at 15:37

Quote: Originally posted by XeonTheMGPony  
proper way is in an all glass amber bottle in a fridge or freezer, I store most my chemicals in the freezer set to the highest temp it will go so -10 or so.

I wrap the glass stopper with Teflon tape rather then grease as well.

I don't have Teflon tape so for now I will just have to put the HNO3 into a round bottom flask with a glass stopper. The HNO3 that has been sitting in the bottle for a while ate through the lid, so I think I may try to make some NC with it since it is too nasty now. Or I may re-distill it.

j_sum1 - 2-5-2016 at 18:48

A bit depends on quantity and how quickly you use it.

I buy peroxide from the pharmacy at ridiculously high prices but the advantage is that it comes in a nice little 100mL amber bottle with a telfon lined cap. So, when I make my nitric acid -- in convenient multiples of 100mL they go in the repurposed bottles. I have not noticed any degradation but I use both the nitric acid and peroxide at a high enough rate that it is easy to give each new batch a fresh bottle and I avoid long term storage.

Camroc37 - 2-5-2016 at 18:56

Quote: Originally posted by j_sum1  
A bit depends on quantity and how quickly you use it.

I buy peroxide from the pharmacy at ridiculously high prices but the advantage is that it comes in a nice little 100mL amber bottle with a telfon lined cap. So, when I make my nitric acid -- in convenient multiples of 100mL they go in the repurposed bottles. I have not noticed any degradation but I use both the nitric acid and peroxide at a high enough rate that it is easy to give each new batch a fresh bottle and I avoid long term storage.

Good idea, I will look out for those. I could've used the HNO3 for something, but I have been trying to save it for making things like ETN, PETN, NG, etc.

woelen - 2-5-2016 at 23:01

HNO3 up to appr. 65% stores very well in reagent bottles with GL45 cap with teflon liner. The drawback of using a glass stopper with a wire to avoid getting stuck of the stopper is the continuous release of fumes, which corrode everything around the bottle.

Nitric acid of higher than 65% simply is a pain in the ass. I do not have such acid, except 40 ml of 95+% acid I made myself. I store this in a 100 ml reagent bottle with red GL45 cap. This bottle in turn I put in a glass jar, filled half way with water and a plastic screw cap on it. This strong acid even goes through the red GL 45 cap and the fumes are absorbed in the water.

A similar problem exists for 36% hydrochloric acid. I limit myself to storing 30% acid, which goes fine in bottles with teflon lines blue GL 45 caps.

Summarizing:

Nitric acid: max. 65%
Hydrochloric acid: max. 30%

Sulphuric acid does not fume at all. Perchloric acid can be stored without any fumes well above 70%.

Loptr - 3-5-2016 at 06:53

Quote: Originally posted by woelen  
HNO3 up to appr. 65% stores very well in reagent bottles with GL45 cap with teflon liner. The drawback of using a glass stopper with a wire to avoid getting stuck of the stopper is the continuous release of fumes, which corrode everything around the bottle.

Nitric acid of higher than 65% simply is a pain in the ass. I do not have such acid, except 40 ml of 95+% acid I made myself. I store this in a 100 ml reagent bottle with red GL45 cap. This bottle in turn I put in a glass jar, filled half way with water and a plastic screw cap on it. This strong acid even goes through the red GL 45 cap and the fumes are absorbed in the water.

A similar problem exists for 36% hydrochloric acid. I limit myself to storing 30% acid, which goes fine in bottles with teflon lines blue GL 45 caps.

Summarizing:

Nitric acid: max. 65%
Hydrochloric acid: max. 30%

Sulphuric acid does not fume at all. Perchloric acid can be stored without any fumes well above 70%.


woelen,

I have not experienced the same problems as you.

I have not noticed any issues with excessive fumes. I have more problems with HCl than I do nitric acid. I only have anhydrous nitric acid at this time, and the lightly greased glass stoppered bottle has done wonders in that storage cabinet. At first there were issues with fumes when I had it in the receiving flask that only had a glass stopper that I had used to prepare it, but then I moved it to an amber colored reagent bottle with a ground glass stopper and the problems ceased. I use Dow Corning vacuum grease in the joint and it seems to work.

I in no way believe that I am more knowledgeable than you, or come anywhere near the experience that you have, and am just curious about the differences in our experience with storage of HNO3.

Herr Haber - 6-5-2016 at 18:58

Teflon tape can be found at any hardware store. Check the plumbing section.

Other than that, red PTFE lined Duran caps are great. Except if you have the pouring ring on and some vapours manage to attack the cap (the liner will be fine though).
I recently wrote about the Duran Premier caps. I love them more and more. The only drawback is that if you keep the pouring ring leakage might occur as stated previously but in this case you wont notice that you have some acid leaking from the cap pushed out by pressure as the cap itself will remain intact.

Conclusion: pouring rings are crap.
I also have Blue Duran caps with a PTFE membrane. I never used them as I'd rather not have HCL / HNO3 vapours floating around and corroding everything in sight.

Yes, I love fluoropolymers !

woelen - 7-5-2016 at 11:28

Quote: Originally posted by Loptr  

woelen,

I have not experienced the same problems as you.

I have not noticed any issues with excessive fumes. I have more problems with HCl than I do nitric acid. I only have anhydrous nitric acid at this time, and the lightly greased glass stoppered bottle has done wonders in that storage cabinet. At first there were issues with fumes when I had it in the receiving flask that only had a glass stopper that I had used to prepare it, but then I moved it to an amber colored reagent bottle with a ground glass stopper and the problems ceased. I use Dow Corning vacuum grease in the joint and it seems to work.

I in no way believe that I am more knowledgeable than you, or come anywhere near the experience that you have, and am just curious about the differences in our experience with storage of HNO3.

Maybe it is difference in climate, difference in quality of glass stopper, difference in storage time.

I am talking about storage for years, not for months. I recently did a major cleanup of my lab, refactoring all bottles of corrosive/fuming stuff. I ampouled all of my PCl5, POCl3, PCl3, NbCl5. I rebottled my nitric acid and 36% HCl. In the long years of storage all of these chemicals were slowly eating their caps and causing corrosion of nearby materials. My most recent loss was a pair of two 12V switching power supplies. They were totally rusted on the outside and did not power up anymore after a short initial glitch. The interior was covered with brown and green mold-like stuff, all oxidized metal from electronic components and metal construction material in the power supplies. After this, I decided to get totally rid of corrosive fumes in my lab.

So, yes, my experiences are different than yours. I hope that you still have the same good experiences after two (or five) more years.

aga - 7-5-2016 at 11:51

Storage of concentrated chemicals is an issue, especially in an amateur setting.

The best way is to try to Plan Ahead, then make just enough really nasty reagents for a series of upcoming reactions, then neutralise/destroy the remainder.

Sounds simple, and it is.

I learned this by trying to store S2Cl2.

One 24/40 ground glass stopper plus the RBF were destroyed for absolutely no nett useful outcome : if i had used the reagent immediately, those items would not be in the bin.

Dr.Bob - 7-5-2016 at 16:35

Another solution for nasty chemicals are reagent bottles with glass stoppers. Not good for bases (they will seize the stopper), but good for acids. I still have a few left. The larger ones are $10, and I still have a few smaller ones for less. I also have some 1L ones with small chips on the top, not affecting the joint, but looking bad, I'd sell those for $5 each.