Talk:Glycerol

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[edit] Random comments at the top

Can anyone give an input on the best method to clean Glycerol from a steel surface? -Inor

What relationship exists between (ethylene or propylene) glycol and glycerin, if any such relationship exists? Do they refer to the same substance?

-Anonymous

Nope. Glycol is 1,2-ethanediol, glycerin is 1,2,3-propanetriol. One more carbon, one more hydroxyl. --Shaddack 00:26, 4 November 2005 (UTC)


Can someone write about using glycerin as antifreeze in cryogenic process? See

http://www.wired.com/news/culture/0,1284,45188,00.html


I changed the entry on 'glycerol and biodiesel' as it cited incorrect info (which is widely distributed thanks to a major error in the poorly researched book "From the Fryer to the Fuel Tank".

The original entry stated that esters are broken off from the glycerol during biodiesel production- in fact, a triglyceride (or a diglyceride or monoglyceride) are esters themselves, and in transesterification, the "vegetable oil" ester essentially becomes a different ester when the alcohols are 'swapped', which we call "mono alkyl esters of fatty acids", or biodiesel. The part of the triglyceride molecule that's broken off is the fatty acid chains- which are not esters in themselves.

-Girl Mark


[edit] frozen temperature

What is glycerol freezing point?

According to the article the melting point (same as freezing point) is 18 °C. --Ed (Edgar181) 14:21, 11 April 2006 (UTC)


[edit] Extracting glycerol

How would you go about extracting glycerol (+ cellulose also) from an insecticide?

[edit] Glycerol Feed Value

What value does Glycerol contain for livestock feed?

[edit] From transesterfication

If biodiesel ismade using ethanol instead of methanol, glycerol isn't produced?

[edit] In biodigesters

Can glycerol be fed to biodigesters?

You might want to try asking at Wikipedia:Reference desk/Science. Talk pages aren't for general questions, they're for discussing the article and how to improve it. —Keenan Pepper 22:58, 22 June 2006 (UTC)

[edit] Triglycerol

Should Triglycerol link to glycerol? I noticed the dead link on Ketosis. Note that Triglyceride and Glyceride are separate pages. Rashad9607 17:03, 1 October 2006 (UTC)

[edit] Purification

This section seems to need cleanup. Was a paragraph recently cut that introduced the procedure concerning methnanol? As stands now it lacks context. I would try myself but lack the specific understanding. 68.53.226.105 16:42, 2 December 2006 (UTC)

[edit] Free glycerol

I've removed this section, which was empty except for a wikilink, because I am unable to see any connection to "free glycerol" at EN 14214. Deli nk 19:11, 24 May 2007 (UTC)

[edit] Extraction of glycerol from fish?

The history channel programe "History's Raiders: Commandos In Norway" document raids against some Norwegian fishing communities where fish processing facilities produced glycerol from fish (used as an ingredient in explosives). Anyone know about the chemistry of this? Electron9 17:57, 5 September 2007 (UTC)

[edit] Animal product

Mention if Glycerol is an animal product or vegan. Jidanni 20:52, 13 October 2007 (UTC)

I think it's a very elementary substance that there's no meaning to its being animal product or of plants.Ai.unit (talk) 21:22, 10 February 2008 (UTC)

[edit] List to prose (applications section)

I have made major changes here: [1]. In summary, I have trimmed the millions of bullet points, and tried to (1) remove duplicates, (2) group similar uses together, (3) write them into paragraphs.

WP is meant to be informative, not exhaustive. There are a whole list of applications which seem rather trivial or minor, which I have removed. I'm dumping them here, such that if anyone can find a way to weave it into the text, with citations, they can do so:

Glycero is consumed by some endurance athletes to counteract dehydration by "glycerol loading" before an event.

  • Used to preserve bacteria at -80 (prevents lysing of cells).
  • Used to increase the density of samples in gel electrophoresis, making them settle in the wells more efficiently.
  • Used in PCR as an additive. It decreases the dielectric constant of the mixture, which will weaken hydrogen bonds in the double-stranded DNA and lower the annealing temperature.
  • When mixed with potassium permanganate, iron oxide, and aluminum, it produces a spontaneous self igniting hypergolic thermite reaction.
  • Used in the conservation of waterlogged organic objects (such as leather and wood) to stabilise before freeze-drying treatment.
  • Used in ink for desktop printers as a viscosity controller and stabilizer.
  • Dropped in eyes to produce fake tears.
  • Used in fog machine fluids
  • Used in hookah tobacco mixtures (called "ma'assel" or "shisha" tobacco), often along with molasses and/or honey.
  • Counteracts phenol burns
  • Manufacture of paper as a plasticizer, nitroglycerin, humectant and lubricant.
  • Used in lubricating, sizing and softening of yarn and fabric
As an additive for alkyd resins (plastics) and cellophane, glycerol is used in surface coatings and paints
  • Used as a softener and plasticizer to impart flexibility, pliability and toughness
  • Uses include meat casings, collagen casings (medical applications)and nonmeat packaging
  • Plasticizer in cellophane.

--Rifleman 82 03:09, 28 October 2007 (UTC)


[edit] Warming effect when applied to skin

Hey - can someone please do a little blurb on why straight glycerin causes this phenomenon? (When applied topically on skin, and especially if air is blown onto it, glycerin makes the skin feel warm.) I actually looked up this article hoping to see a scientific explanation for this. Tx! Sugarbat (talk) 22:30, 23 January 2008 (UTC)

I'm not sure about this, but most probably it's the energy released when glycerol is combined with water.. I don't really know what you call this in english, but it's known in chemistry as the energy released by solving into water.
Air carries moisture, especially when you're blowing your breath (which has high moisture content). To prove this, test by adding some glycerol drops to a small amount of water and feel how it rises in temperature. Ai.unit (talk) 21:19, 10 February 2008 (UTC)
Wow -- that's a great explanation. It never occurred to me to test it in such a simple way, which makes me feel dumb. I did actually want to know whether the warming was actual or was perhaps a reaction of the skin (histamines? etc.) that *feels* like warmth, but isn't, actually (like how your mouth feels hot after you eat a curry, but isn't really hot). You're saying that there *is* in fact a rise in temperature when glycerine hits skin (or, technically, the water in/on skin), and/or when it's on the skin and is also blown on with breath, and that's why it feels warm -- because literally it is. Thank you. :) Sugarbat (talk) 17:37, 29 April 2008 (UTC)


[edit] Refractive Index

Isn't glycerol's refractive index close to that of glass (pyrex) and hence creates odd illusions when combined Thomashauk (talk) 01:31, 24 May 2008 (UTC)