Just curious, Will PETE resist concentrated H2SO4? Every time I search google for information on this polymer I conveniently get information on HDPE
or PE in general.
Anyways, I've been having a hell of a time finding air tight containers to store my 92% Sulfuric acid, and I want to use a 2 liter pop bottle to
solve this problem. Any advice would be greatly appreciated.
While I'm on the subject does anyone know if PETE will resist 35% H202?
[Edited on 14-7-2004 by tom haggen]tom haggen - 14-7-2004 at 18:38
Quote:
PET is Semi-rigid to rigid depending on container wall thickness. Good to fair chemical barrier; not good for strong acids or bases. Good alcohol and
solvent barrier; good gas and fair moisture barrier. Good moldability. Sterilizable through EtO and gamma radiation. PET bottles and jars have good
stress crack and impact at room temperature and above.
Ok I think this answers my questions about strong acids as a no. But what about 35% H2O2.Cyrus - 14-7-2004 at 21:57
I have no clue, but I bet there is one simple way you could find out.
Also, I would never store anything in a lowly pop bottle out of principle. Eventually you might forget which chem. are compatible, and then
you've got some chemical all over your store room. Why not use a wine bottle and a teflon wrapped wine bottle cork, the bottle is then sealed in
a plastic bag which has a dessicant at the bottom? That ought to hold acid in, water out.
Edit, according to Flinn
"Polyester plastic, from which most 2-liter soda bottles are made, is a particularly poor choice, since both acids and bases quickly attack it.
Strong oxidizing agents also cause many plastics to become brittle and crack. While extended storage may not be intended at the time you fill the
container, a forgotten container will fail."
Edit again, my nagging conscience is telling me "liar, liar."
Ok, I confess, at one time in the distant past I put things in pop bottles.
[Edited on 15-7-2004 by Cyrus]
[Edited on 15-7-2004 by Cyrus]thunderfvck - 15-7-2004 at 00:22
I store my >90% H2SO4 in a wine bottle. It's been sitting in there for a few months and nothing seems to be going wrong.
As for the 30% H2O2, I store it in the brown plastic container I bought the 3% in. That also seems to be working quite well!tom haggen - 15-7-2004 at 08:29
I guess a wine bottle is good in theory. However, I don't drink wine, I'm not going to go buy a bottle of wine and dump it out just for a
container, and I don't like the Idea of manufacturing my own cap out of cork and teflon tape and I'll tell you why. I have had nothing but
problems when trying to get a good seal using a teflon tape lid. Basically I just haven't been able to find any good HDPE containers lying
around the house that will hold a good seal. It's quite frustrating. I think I'm just going to go down to the grocery store and try to
find a good HDPE container down there. You are wrong about pop bottles they are not made out of polyester plastic. They are made out of PETE
(Polyethylene terephthalate), but like I stated in a post before you they will not resist strong acids and bases. By the way whats all this non-sense
about pop bottles making you forget what chemcials you have? Have you ever herd of labeling your containers I just like pop bottles because the make a really good seal at the cap, and they are large.
[Edited on 15-7-2004 by tom haggen]Cyrus - 15-7-2004 at 11:42
I wasn't wrong about pop bottles. I know they are PETE. I just quoted Flinn, which while being wrong about most things, had a good point IMO.
Oh, I was not saying that you might forget what was in your bottles, I hope you label them, I was saying you might forget which chemicals are
compatible with PETE and accidentaly put an incompatible chemical in a pop bottle, causing it to fail.
You need to use lots of teflon to get a good seal. I wrap the teflon so that it is about 5-15 ply in the critical areas.
What! You don't drink wine? It's good for ya! Get a wine bottle from a neighbor's recycling bin.The_Davster - 15-7-2004 at 12:03
Most people return their wine bottles to the "bottle depot" and get a few cents for it so I dont think that people will be throwing them
out.thunderfvck - 15-7-2004 at 12:41
I have a 4 L wine bottle, quite the behemoth. I'm boiled down all my battery acid to fill that sucker up. It has a cap that was used for a HDPE
bottle, so I think I'm doing good.
Restaurants go through wine bottles like water, and they throw them out. You could ask them. Or you could spend $10 on a bottle of wine...then drink
it all and get NICELY drunk. Always fun.tom haggen - 15-7-2004 at 16:21
Well I think I'm just going to go down to the store and try to find a water tight HDPE container. Now If I were storing HNO3 than a wine bottle
would probably be my choice. Damm 4 liters of concentrated H2SO4. Isn't it amazing how heavy that stuff is. I got about 1 liter right now and
everytime I pick it up I'm like Damm.BromicAcid - 15-7-2004 at 16:28
I left 30% H2O2 in a pop bottle for about 15 hours and there was no sign of attack. However on a different occasion I put 70% HNO3 in a pop bottle.
The next day the pop bottle was deformed like a torch was taken to it, it was leaking, porous, and brittle. I will never store strong oxidizing acids
in pop bottles again. (Actually I have never used pop bottles for extended storage, only to bring a small amount of a chem from point A to point B
when I don't feel like bringing the whole reagent bottle, still not a good move though.)tom haggen - 15-7-2004 at 19:34
I wonder if PETE will resist H2SO4 since it's not an oxsidizing acid???Polverone - 16-7-2004 at 11:22
I highly doubt that PETE will resist concentrated H2SO4. If you want to prove me wrong, please keep your plastic bottle of acid sitting in a glass pot
or something for a week while you see how it holds up. In any case, H2SO4 is an oxidizing acid, though not as oxidizing as some. Consider its reaction
with bromides and iodides, as well as its effects on copper, carbon, sulfur, and other materials at elevated temperature.
PETE and H2SO4
Organikum - 16-7-2004 at 15:45
Pop bottles made from PETE dont resist conc. H2SO4. This was tried and failed.
HDPE works well - at least the over 94% strong H2SO4 is sold in strong HDPE bottles, as is 30% H2O2 and 32% HCl.
I cant understand the problems with caps. Winding PTFE tape in enormous layers on a cork? Huh? Take a piece of not to thin PE-foil, put it on the
bottle and press the cork in. Bingo, PE cap, custom made.
Works.
For fuming mineral acids I would advise to invest in the real things for storage. With grounded joints and all this fancy stuff. H2SO4 with 50% SO3 or
70% HI - all sloppyness ends here or you will pay the price in pain.
Plus interest, is understood.tom haggen - 16-7-2004 at 18:34
Due to the hydroscopic nature of H2SO4 I would be suprised if you could really manufacture a cap with a good seal. I definitely had problems storing
70% nitric acid with a homemade cap. I have one small HDPE container that seals very well.
But I need a large one my days of fantisizing that PETE will resist concentrated
H2SO4 are over. Thanks for the help everyone.tom haggen - 2-8-2004 at 19:36
So I kinda found a half assed suitable HDPE container to hold my Strong sulfuric acid for the time being. Anyway, the acid seems to be staining the
inside of my container a dark yellow color. The acid also appears to be turning a darker color itself. Anybody know what type of minute reaction is
taking place between my acid and my HDPE container? I assume its a very small amount of oxidation?
[Edited on 3-8-2004 by tom haggen]JohnWW - 2-8-2004 at 23:45
I am not sure exactly what polymer PETE is; but if it is a polyester, or a polyamide (like nylon), there is a possibility that concentrated H2SO4
would hydrolyse it, and then form a sulfonate. On the other hand, if it is a polymer of an unsaturated hydrocarbon, or of an unsaturated halogenated
hydrocarbon, it should be impervious to H2SO4.
John W.tom haggen - 3-8-2004 at 05:00
Ya thats great but my last post was about HDPE....unionised - 3-8-2004 at 13:00
Last time I checked
(1) this thread was about PETE
(2) HDPE was a polymer of an unsaturated hydrocarbon.tom haggen - 3-8-2004 at 15:16
Ok, rather than start a whole new thread about acid resistant polymers, I figured I would try and hit 2 birds with one stone. I'm well aware that
HDPE has great resistance to sulfuric acid. However, when I've done syntheses with a small HDPE cup that comes with Nyquil. I noticed some
stains that formed on the polymer. I've been noticing the same stains on the HDPE container I'm currently using to store highly
concentrated H2SO4. I've stored H2SO4 in other HDPE containers with out this problem. Any idea what is taking place? Oxidation no? If this is
the case, won't this be breaking down my acid slowly but surely?
[Edited on 3-8-2004 by tom haggen]chemoleo - 3-8-2004 at 16:08
To my experience, don't use ever any plastics for conc. sulph acid. The acid will get black, and how fast it gets black is a question of time
only. Org - I read you. My 98% H2SO4 also came in HDPE bottles originally. After 5 years or so, the colour of the acid turned noticably black/dark
(yet clear).
For that reason I once went to the pharmacy and bought some nice glas bottles - and never had a problem again thereafter.
(Besides this, it's a saftey risk - you wouldnt want one of these plastic bottles leaking, dripping onto a metal container containing NaClO3
below! ... this is my personal horror scenario btw)
PS what the hell IS PETE? polyethylenewhat? HDPE is High Density PolyEthylene presumably?
[Edited on 4-8-2004 by chemoleo]tom haggen - 3-8-2004 at 17:30
PETW- Polyethylene Terephthalate, it's a transparent polymer often used by soft drink manufacturers.
[Edited on 4-8-2004 by tom haggen]palpy - 4-8-2004 at 14:52
PETE = PETP = PET (the latter being used in europe)
quote: "You are wrong about pop bottles they are not made out of polyester plastic. They are made out of PETE (Polyethylene terephthalate)."
???
just judging by the name, Polyethylene terephthalate is a polymeric ethylene salt of terephthalic (p-phthalic) acid, thus a POLYESTER, or am I
wrong?... tom haggen - 4-8-2004 at 21:48
my days of fantisizing that PETE will resist concentrated
H2SO4 are over. Thanks for the help everyone.