Nickbb - 20-1-2013 at 17:23
Are there any common plastics that can store nitric acid around 98% conc.? I looked at several plastics and none were said to be resistant to it. I
was wondering because glass bottles aren't cheap and plastic bottles are so easy to come by.
kristofvagyok - 20-1-2013 at 17:45
98% HNO3 may ignite on contact with most plastics (PE, PS, HDPE, PP ect.). It could be stored in a PTFE bottle, but I think glass is much cheaper.
Save your money, but not on your safety.
plante1999 - 20-1-2013 at 17:47
I already stored 10 ml yellow fuming nitric, 98%+ (that was able to make nitril catch fire) In a 15 ml Nalgene polyethylene bottle with polypropylene
cap (the one that cost 3$ each) and it did a good job. After 8 month it was still ok. I think the heavy nalgene p.e bottle are surface fluorinated.
Vargouille - 20-1-2013 at 17:56
Depends on your definition of "common". According to Harrington, the materials that will withstand (red) fuming nitric acid are Halar (a trademarked
plastic good to about 80C), PTFE (to about 175C), carbon, ceramic, 304 stainless steel (something I find rather odd, considering that 316 stainless is
unsuitable), and Hastelloy C. Incidentally, Viton has no data.
I'd suggest splurging on the glass bottles and some high-quality teflon-lined caps.
kristofvagyok - 20-1-2013 at 17:58
There was 50cm3 95% HNO3 in a glass bottle with a standard PE cap. The cap cracked after 2 week and just "died" a few days later. Just the NO2 fumes
was identified....
We've got several liter of 100% HNO3 and all is stored in polymer coated breaksafe glass bottles with PTFE caps and is kept in diatomeous earth.
I would not pour +95% HNO3 again in a bottle that could give up in any time, it could cause surprise in any time.
Sublimatus - 20-1-2013 at 18:13
One thing to consider is NO<sub>x</sub> gases building up inside of whatever container you use.
I recall the first time I synthesized HNO<sub>3</sub>, I stored it in a brown Boston round bottle with a PTFE lined plastic cap. I forgot
about it for a few months, and the next time I went to use it I noticed that the cap seemed cracked. I found this perplexing, since I couldn't
imagine how the acid fumes might have gotten past the liner to attack the cap.
Of course when I unscrewed the cap, a mist of NO<sub>x</sub> and nitric acid blew out around the mouth of the bottle as the pressure
equalized. I was rather surprised, since I hadn't considered that the cap was cracked due to internal pressure. In hindsight it's fairly obvious what
I had in my hands.
These days I have my nitric acid in a Schott Duran bottle with a more robust red PBT cap and PTFE liner.
The NO<sub>x</sub> gases may not be a concern for purified and commercial nitric acid. However, it's clearly something to think about
with homemade acid (mine was clear after synthesis, but with time has turned orange).
[Edited on 1/21/2013 by Sublimatus]
Nickbb - 21-1-2013 at 18:19
Thanks for all the replies... I guess it is best to stick with glass bottles, I like them better anyways and I just picked up several of them for a
dollar and a half at a organic grocery store (who knows why they sell them..) Also thank you for that piece of information there Sublimatus; I'll have
to remember to vent the bottle every now and then if I keep it around for long enough.