What are some blue organic compounds?

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Discussion Overview

The discussion revolves around the unexpected appearance of a blue liquid produced during the distillation of wine into ethanol. Participants explore potential causes for the coloration, including the materials used in the distillation setup and the nature of the original wine.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes distilling wine into ethanol and obtaining a blue liquid, raising concerns about its composition and safety for use as windshield washer fluid.
  • Another participant suggests that the blue color may be due to copper, questioning whether any copper fixtures were used in the distillation setup.
  • Concerns are raised about the cleanliness of the distillation apparatus, with one participant noting that impurities could have leached into the ethanol during the process.
  • A participant mentions that the color is removed after passing through a Brita filter, which could indicate the presence of copper or organic compounds.
  • There is speculation about the possibility of volatile sulfides corroding the copper condenser, leading to the blue coloration.
  • Questions are posed regarding the size of the alcohol fraction from the first distillation and the efficiency of the distillation process, with suggestions to boil the product dry to assess dissolved solids.
  • The original poster provides details about the wine's age and the distillation process, indicating that the second distillation yielded a product with over 90% ethanol and no visible residue.

Areas of Agreement / Disagreement

Participants express various hypotheses about the cause of the blue coloration, with no consensus reached on the exact source. Multiple competing views regarding the potential role of copper and impurities remain evident throughout the discussion.

Contextual Notes

Participants acknowledge limitations in their distillation setup, including the use of a plastic condenser and the potential for poor separation during the distillation process. The discussion does not resolve the uncertainties surrounding the chemical nature of the blue liquid.

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.

http://myfiles.dyndns.org:8080/junk/pictures/shawn_projects/blue_ethanol.jpg
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.
 
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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?
 
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.
 
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.
 
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.
 
Bystander said:
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.
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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