Sciencemadness Discussion Board

Glass storage problems with 93% sulfuric acid

ninhydric1 - 17-3-2018 at 14:15

I recently purchased 1 L of 93% sulfuric acid drain cleaner. I then transferred the sulfuric acid to 2 500 mL amber glass bottles. But when I came back to the lab 1 hr later, it seems like as if the acid was leaking from the bottle (note that I filled the acid to the top of the bottle; therefore, each bottle contained about 800 g of liquid). I'm pretty sure it's not a residual acid drop on the outside because both bottles exhibited leakage, and I only spilled a drop on one of the bottles. Currently, I've returned 500 mL of the drain cleaner back to its original bottle (it's HDPE, so I need to find a solution, fast), lessened 250 mL of liquid in both containers. Any advice for such storage?

aga - 17-3-2018 at 14:19

Immediately use or throw out about 100ml of the acid.

= Fill bottles less full (headspace)

ninhydric1 - 17-3-2018 at 14:27

Yeah, that's why I reduced it to 250 mL per 500 mL glass bottle. I might need to buy more then :mad:.

EDIT: Note that I've never had more than 125 mL of concentrated sulfuric acid (I've been surviving off it for the past year), so I'm sounding a bit like a newbie.

[Edited on 3-17-2018 by ninhydric1]

aga - 17-3-2018 at 14:48

Quote: Originally posted by ninhydric1  
I recently purchased 1 L of 93% sulfuric acid drain cleaner. I then transferred the sulfuric acid to 2 500 mL amber glass bottles...

Full Bottles. Very full. Too Full.

Use HDPE. Works fine for this.

UberNoob, Obi-Wan-Chemobi ...

Shit happens.

Edit:

As an aside, i got a lot of 56% H2SO4 and generally boil it down until it Fumes, then regard it as 98%.

This lot is clear. Previously it was brown drain cleaner stuff.

Adding Cold 3% H2O2 when it was very very hot was absolutely no problem.

No explosion, no kidney failure, no loss of body-parts, nothing.

The whole acid-to-water thing is silly IMHO.

[Edited on 17-3-2018 by aga]

ninhydric1 - 17-3-2018 at 15:48

I won't be cleaning it anytime soon; it looked crystal clear straight from the bottle so it will be fine for now. I'll truly clean it in the near future.

Deathunter88 - 17-3-2018 at 21:19

Quote: Originally posted by ninhydric1  
Yeah, that's why I reduced it to 250 mL per 500 mL glass bottle. I might need to buy more then :mad:.

EDIT: Note that I've never had more than 125 mL of concentrated sulfuric acid (I've been surviving off it for the past year), so I'm sounding a bit like a newbie.

[Edited on 3-17-2018 by ninhydric1]


No need to leave so much headspace. 475ml in a 500ml bottle is more than adequate. 450ml if you are truly worried.

Ubya - 18-3-2018 at 09:29

but if the bottles are upright and not cracked why would they leak?

[Edited on 18-3-2018 by Ubya]

ninhydric1 - 18-3-2018 at 12:48

Too much mass I suspect. 500 mL of H2SO4 is nearly 1 kg of liquid. It might've cracked, so I split up the acid into 250 mL portions, put it into 2 new 500 mL bottles, and am going to test the two original bottles for leakage now.

XeonTheMGPony - 18-3-2018 at 13:21

I invested in a 1L reagent storage bottle for my stuff, well worth it.

MrHomeScientist - 19-3-2018 at 13:18

Another argument for less headspace is that you limit the surface of the liquid in contact with air, which slows down any degradation from reaction with atmosphere. In this case, slow dilution by absorbing water. Granted that would be REALLY slow, but it can be something to consider for other reagents that like to form explosive peroxides, for example.

Sulaiman - 19-3-2018 at 13:50

If concerned with headspace you can use a collapsible/concertina bottle


https://www.sigmaaldrich.com/catalog/product/aldrich/z162094...
collapsible.jpg - 23kB

I have one from wet photography days, still OK but I do not trust repeatedly flexed plastic with 'nastier' liquids like conc.sulphuric acid.

JJay - 20-3-2018 at 09:22

I keep clean, titrated and distilled sulfuric acid in Boston round bottles with Qorpak PTFE-lined caps, 400 mL per 16 oz bottle. I keep drain cleaner in the hardware store jugs, which are HDPE. Sulfuric acid does appear to degrade HDPE very slightly over time.