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What are some blue organic compounds?

  1. Dec 3, 2005 #1

    ShawnD

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    I distilled some horrible tasting wine to make it into a usable windshield washer fluid (it's just ethanol with some horrible tasting organic things). The wine started as a light yellow color, and it distilled into a colorless clear liquid. Ok that's good, ethanol is supposed to be colorless. This is an inefficient column though, so I ran that product through again to make it more pure, but this time I saturated it with NaCl to make it work better (increase ethanol partial pressure, lower water partial pressure). The product of this distillation was blue in color. I started with a colorless liquid and some salt, and I got a blue solution. I obviously won't put this into my car unless I know what it is.

    [​IMG]
    It has a very very strong smell to it. Almost smells like ammonia.
    edit: this blue liquid is the very first cut to come from the distillation. It accounts for maybe the first 10-20% coming off.

    Any suggestions at all would be greatly appreciated.
     
    Last edited: Dec 3, 2005
  2. jcsd
  3. Dec 4, 2005 #2

    movies

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    When I see something that color, my first thought is copper. Did you have any copper fixtures in your distillation setup?

    Also, that tubing looks a little nasty. Are you sure it was clean? You may have had some junk that wasn't soluble in water, but then leached out when ethanol went through it.

    What was the boiling point of this stuff?
     
  4. Dec 4, 2005 #3

    ShawnD

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    The condenser is made of copper. The rig was cleaned by running hot water through it for a few minutes.

    I don't know the boiling point of this stuff because my rig is really half-assed, but I can say the color is completely removed in 1 pass through a Brita filter. Brita filters are just charcoal with some cation exchange resin, so it would remove copper or organic colored things.
     
  5. Dec 4, 2005 #4

    movies

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    Yeah, I would bet that it was some copper salt junk. Glass is really the way to go if you can get ahold of it. I wonder if there were some volatile sulfides in your stuff that corroded the copper.
     
  6. Dec 4, 2005 #5

    Bystander

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    What size was the alcohol fraction from your first distillation? From your picture, you got 7-8 oz. from the second, which is either a helluva big bottle of wine to start, or a zero reflux rate for the distillation. Meaning you boiled a load of salt through the condenser tube, hence the blue.

    Boil it dry if you want to see how much dissolved solids were carried over in your distillation process.
     
  7. Dec 5, 2005 #6

    ShawnD

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    It was a few bags of home made wine from 1978. It tasted absolutely horrible. The first distillation gave rather crummy separation, I can tell by the beads of water in the upper part of the plastic condenser (there's a plastic >> copper connection). The second distillation gives good separation, and the distillation stops when water beads form in the plastic part of the condenser. Water beads, alcohol does not. The product is over 90% ethanol (by hydrometer) and it burns to completion with no water (or salt) residue.

    I guess I'll be more careful with the salt next time. Thanks for all your help! :smile:
     
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