Sciencemadness Discussion Board

95% ethanol + plastic

flyingbanana - 17-7-2005 at 12:15

Will one of those thin plastic gallon milk/water containers hold 95% ethanol? Will the plastic dissolve a little bit, so the ethanol is contaminated? And, are those containers thin enough that the ethanol will slowly evaporate over time through the plastic?

chemoleo - 17-7-2005 at 13:05

No, if it is HD PE.

96 % ethanol is delivered in HD - PE bottles and stores just fine (personal experience).

Nonetheless maybe you should get something less flimsy than milk containers.

my nootloss - 18-7-2005 at 20:49

If you’re not sure what plastic it is look at the recycling code (number) and then look it up. Or you could take a drop and try it, if you distilling it then try it like the first time you distill it so that you will know. Also you can look up an msds, and that will tell you.

unionised - 19-7-2005 at 12:22

How does one find the msds for a milk bottle?

my nootloss - 19-7-2005 at 14:25

Quote:
Originally posted by unionised
How does one find the msds for a milk bottle?


Oh this is how to find the msds for a one-gallon milk container (good day reduced fat milk 2%)


1st after drinking/using all the milk and cleaning out (as to not get drips on the floor). Turn it over. Then read what it says (say’s #2, which is hdpe plastic).

2nd type “msds hdpe” in to google.com, under the search web category

4th read the msds

Edit: Forgot to say click on the (appropriate) link for number 3.

[Edited on 19-7-2005 by my nootloss]

cyclonite4 - 19-7-2005 at 18:52

I'm actually in the process of building a still aswell. Does anyone know if PET (polyethylene terephthalate, used for soft drink bottles) is resistant to ~95% Ethanol?

I've found a MSDS for PET, but it has hardly any information in it. After googling I've found nothing about PET's reistance to ethanol (I searched by expanding PET to its full name, so as not to confuse google with the word 'pet';).

Anyone here with personal experience of storing in PET (coke) bottles? I don't want to store it in there myself to find the plastic has leeched into the distillate.

unionised - 20-7-2005 at 12:51

My nootloss, I trust that you had a bit more success with that search than I did.
1 page that won't load properly, in Korean (I think).
What I was getting at was that you need a chemical compatibility chart for HDPE rather than a MSDS.

neutrino - 20-7-2005 at 13:42

A chemical resistance chart should tell you what you need to know. The problem is that those usually seem to be written for materials more resistant to chemical attack. Try searching, though, you'll probably have better luck than I did when I came to this conclusion.

Polypropylene

chloric1 - 21-7-2005 at 12:04

PP is cheap and widely available. Lab grade bottles of this polymer can be bought without suspicion. I remember back in 97 or 98(not sure when exactly) I had some PP scrap and I was trying various solvent to make a liquid so I could use it for coatings. Both acetone and xylene only made the surface tacky and an hour of immersion in xylene at 25 degrees C had negligable results! I am positive this would work for your ethanol.

12AX7 - 21-7-2005 at 12:31

PP is pretty inert stuff. Damned near impossible to bond, too! It appears to melt easily (light a strip of it some time), but as with all plastics, tight temperature control will be needed to keep it from cracking the molecules, and that low temperature is probably at best quite viscous, requiring high pressure to inject it. If you are looking to mold it, that is.

Tim

[Edited on 7-21-2005 by 12AX7]

neutrino - 21-7-2005 at 15:40

Speaking of bottles, one can always get 1L HDPE bottles at photo stores (they're used for reagent storage.) I'm not too sure about the purity, though, as they aren't designed for food use.

Why not empty bottles/jars? I know that mayonnaise jars come with PP caps.:D

Oxidizers a different matter

chloric1 - 22-7-2005 at 09:18

In the past I have had the little 1 oz and 4 oz PP dropper bottles that I use to store dilute HCL,HNO3,& H2SO4. These acids are of no action in half dilution and they are handy when working with heavy metal salts when slight hydrolysis happens upon solution.

But I have personally seen these bottles blister, turn yellow, and become brittle in prolonged exposure to extreme oxidizing conditions. Two instances involve mixed acid(Conc HNO3 & H2SO4) and Chromic acid solution. I also suspect a simular action would be noticed in fuming nitric acid, free halogens, covalent halides and oxyhalides,ozone, and other aggresive agents. But, these agents can be stored temporarly while a more suitible container to procurred for long term storage

hAzzBEEn - 22-7-2005 at 13:23

From Homedistiller.org:
Quote:
Plastic
Plastic is basically fine at the low alcohol end (eg the wash, and even the diluted product), but if possible, try to avoid using it where it is likely to encounter strong alcohol. For alternatives, consider using copper tubing from the condensor to the collection jar, and using glass collection & storage jars.

Quote:
Coulson, Richardson & Sinnott report that:
  • aluminium, aluminium bronze, brass, copper, gunmetal and bronze, high Si iron, nickel, nickle-copper alloys, platinum, silver, stainless steel (18/8, molybedenum & austenitic ferric), titanium, tantalum, and zirconium
  • nylon 66 fibre & plastics, PCTFE, PTFE, polypropylene, and furane resin
  • hard rubber, neophrene, nitrile rubber, chlorosulphinated polyethylene, and silicone rubbers
  • concrete, glass, graphite, porcelain and stoneware, and vitreous enamel

are corrosion resistant to alcohols, beer & water up to 100C.

  • lead, mild steel (BSS 15), cast iron, and tin
  • acrylic sheet (eg perspex), acrylonitrile butadiene styrene resins, rigid unplasticised PVC, plasticised PVC, polyethylene (low & high density), polystyrene, melamine resins, epoxy resin, phenol formaldehyde resins, polyester resins
  • butyl rubber & halo-butyl rubber, ethylene propylene rubber, soft natural rubber, and polyethylene rubber
  • wood

are not corrosion resistant to them. Now I don't know too much about toxicity...


This was from Nalgene Bottles For Storing Final Product ? thread on the Homedistiller message board:
Quote:
Glass good--plastic bad. We've had tons of problems with high proof distillates we recieve in plastic. Many of our clients are in Latin/South America or Asia, and seem to want to save money by using plastic. It often gives a pesticide smell to high proof spirits. The only one I would recommend is polycarbonate, and then only for diluted spirits (i.e. 40%). This is the crystal clear plastic that many of the distillers are now using. Nalgene, sorry, but no!

Hope this helps.