Sciencemadness Discussion Board

Storage and purification q's

Camroc37 - 10-9-2015 at 16:44

Several questions, all different:
1) I made Copper Nitrate using Copper Carbonate and Ammonium Nitrate. How can I purify it? (Will re-crystallization work?)
2) How do you all store chemicals? What kinds of containers? (NurdRage has a video showing a chemical being stored, but it was an expensive molecule and thus a small container).
3) Will Polypropylene resist H2SO4, HCl, and HNO3?

--I would like a clear container, but made of what? Glass, Plastic, or...

elementcollector1 - 10-9-2015 at 16:54

1) Yes, recrystallization will yield purer crystals. The more times you recrystallize it (properly!), the purer it gets (and the less you have).
2) I use plastic containers, specifically these.
3) Engineering toolbox says no.
Go for glass, or whatever it is those Rooto containers are made out of.

gdflp - 10-9-2015 at 17:03

Quote: Originally posted by elementcollector1  
whatever it is those Rooto containers are made out of.

That would be high density polyethylene, or HDPE. It withstands conc. hydrochloric acid and conc. nitric acid, but for long term storage of sulfuric acid over 80%, I would go with glass containers. In regards to salts, HDPE resists attack from most common inorganic solids, bar polymerised sulfur trioxide. As long as you don't mind the containers being translucent or opaque, HDPE is a good, chemical resistant, and less fragile alternative to glass. It is not, however, suitable for use with most organic solvents.

Camroc37 - 11-9-2015 at 16:28

Quote: Originally posted by elementcollector1  
1) Yes, recrystallization will yield purer crystals. The more times you recrystallize it (properly!), the purer it gets (and the less you have).
2) I use plastic containers, specifically these.
3) Engineering toolbox says no.
Go for glass, or whatever it is those Rooto containers are made out of.

Thanks. You know you linked a sample of silicon instead of a container, right? I will look on United Nuclear then. I don't think I've considered them for containers.

Camroc37 - 11-9-2015 at 16:29

Quote: Originally posted by gdflp  
Quote: Originally posted by elementcollector1  
whatever it is those Rooto containers are made out of.

That would be high density polyethylene, or HDPE. It withstands conc. hydrochloric acid and conc. nitric acid, but for long term storage of sulfuric acid over 80%, I would go with glass containers. In regards to salts, HDPE resists attack from most common inorganic solids, bar polymerised sulfur trioxide. As long as you don't mind the containers being translucent or opaque, HDPE is a good, chemical resistant, and less fragile alternative to glass. It is not, however, suitable for use with most organic solvents.

forgot about HDPE!

fdsailor - 22-9-2015 at 17:32

I have a somewhat related storage question - in my simple (and small - most things in liter quantities) acid storage, I am storing the bottles of HCl, H2SO4 and HNO3 together in a large plastic "closetmaid" tub with a loose fitting lid - the idea being that a) it keeps them on the ground, and b) there is some secondary containment if something breaks.

But the annoying part of the arrangement is with the HCL - currently stored in HDPE, no matter what you do, it outgasses - and this seems to join with condensation presumably from air to lightly coat everything in what I am assuming is mostly HCL of some concentration. And of course, I'm sure some HCL vapor escapes with intent to rust my tools, etc. I know HCL is very soluable in water, but is there any "superabsorbant" I can place in the box to scrub up as much as the HCl (g) as possible to minimize these secondary effects? Otherwise - HCl is going into lots of glass containers, but.. those are certainly not free.

elementcollector1 - 22-9-2015 at 18:49

1) Place HCl in bucket labeled "Acids".
2) Line bottom of bucket with small amount of baking soda.

That's what I did, and it ended up working just fine.

Sulaiman - 22-9-2015 at 23:44

I keep bulk (0.5, 1.0, 2.5 l) HDPE bottles of concentrated acids and bases in the same 60l plastic tub.
The ammonia fumes seem to cancel the HCl fumes, leaving white dust ! :P

ave369 - 23-9-2015 at 00:07

I keep my acids in the same cabinet as ammonia and salt of hartshorn. Again, fumes appear to cancel each other.

byko3y - 23-9-2015 at 11:20

Quote:
Yes, recrystallization will yield purer crystals. The more times you recrystallize it (properly!), the purer it gets (and the less you have)

I was lucky to work with copper nitrate, and boy this stuff is nasty. It decomposes on boiling, while gives off fumes of NO2 if acidic. Universal indicator papper turned red lying one meter away from the flask with evaporating nitrate copper.

Little_Ghost_again - 23-9-2015 at 15:34

My copper nitrate seems deliquescent?? I had to use a desiccator to get crystals.