Talk:Ethanol

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[edit] Absolute Ethanol

Under Absolute Ethanol:

"Absolute ethanol is often denatured by adding watermelon juice, which in fact, is further distilled to make Midori, a drink favored by the Japanese."

I think this should be omitted.. either that, or leave it as "Absolute ethanol is often denatured by adding watermelon juice, which in fact, is further distilled to make Midori." without "a drink favored by the Japanese." --j4m3sb0nd 25 March 2007 (UTC)

[edit] How does ethanol denature proteins and lipids?

Would it destroy hemolymph? Chiss Boy 00:16, 20 March 2007 (UTC)

[edit] questions about industrial dest.

The article states that addition of benzene to ethanol is a common industrial way to produce ethanol absolute. And later it says, that other methods (glycerol, CaO, etc etc ) are quite common. This strikes me as weird. I don't know which procedure is more common at the moment, however, I contend that the 3 ppm benzene in EtOH would not harm a fly, even in a lifetime of drinking (yes, subjective... sorry) Sikkema 21:28, 18 January 2007 (UTC)

[edit] As a Fuel, serious NPOV issues

The article previously stated that 'production of ethanol is "easy" (through fermentation of sugar via sugarcane) and is environmentally benign. This was changed for NPOV and since the production of pure sugar is one of the most detrimental things people can do aside from pumping flurocarbons into the air.^[1] As a fuel we're essentially doing both of these, but you don't see me stating this in the article. However those who go about stating things are environmentally begnign without knowledge of what they are in fault due to wrong information and NPOV.

I agree: A more specific thermodynamic analysis, as seen often in literature (don't have the refs) shows that ethanol as "biofuel" is by far not as efficient and "green" as widely thought. Something MUCH more efficient is the installation of solar cells. Sikkema 21:11, 18 January 2007 (UTC)

[edit] Brewing

changed the level of alcohol the strongest yeasts can survive from around 20 to 25%, as Samuel Adams has recently come to market with a non-distilled 50 proof beer using a super yeast they have been developing for decades.

I've so far been unable to find the source of this information. Is there something that can be cited? Nahaj 21:01, 26 June 2006 (UTC)

[edit] Name

Why is the name of the article Ethyl alchohol and not ethanol. Ethanol seems to be the name consequently used in the rest of the articleFornadan 06:59, 30 Jan 2005 (UTC)

I support a move to article title ethanol. Physchim62 20:49, 29 May 2005 (UTC)

"and that the economic irrationality of using grain-produced ethanol to replace petroleum can be seen from the fact that almost all industrial ethanol is produced from petroleum feedstocks" -- removed this because I don't understand the illogic -- Marj Tiefert 17:11 Aug 6, 2002 (PDT)

Uhm it makes sense, if indusrial grade alcohol is made from petroleum because its cheaper than grain why would you want to replace petroleum with grain-alcohol?

I have been annoyed by advertizments on Public Radio's News Hour by Arthur Danial Midland that imply that ethanol is their exclusive product made from corn. Some writers have expressed concern that ethanol as an additive to gasoline might be poisin if spilled into the ground water like the synthetic MTB. [daviddibble@aol.com]

Perhaps because petroleum is a finite resource and also prices are volatile? user:sjc

I wasn't arguing with the sentence, i was just reiterating it because marj found it illogical. It actually makes sense though, and that was what i was trying to say. It IS economically irrational to replace petroleum with ethanol when you consider the most cost-efficient way of producing ethanol is form petroleum feedstocksLightning 14:28 Oct 14, 2002 (UTC)

"Most alcoholic beverages are not useful to replenish the body's fluids, since they cause the body to lose more fluids as urine than are taken in by the beverage."
What is 'most'? Historically in Europe, alcoholic beverages were the only safe things to drink, and many/most? people drank only/majorly? beers & wines for their liquid intake. How does that compare to this statement?
~ender 2003-08-30 20:54:MST

I'm not certain what you're referring to. I find it unlikely that alcoholic beverages were ever the major part of a person hydration, and it seems useless. Alcohol, in any form, is diuretic. I suppose if it was watered down enough, it would be possible to drink more water than you would lose in urinating, but this wouldn't address the problem of water being unsafe to drink, except inasmuch as alcohol kills bacteria. AFAIK, the word most is incorrect, since all alcohol is diuretic. Tuf-Kat

I remember reading somewhere that letting substances ferment was one way to make them safe to drink. In Asia however they used to boil liquid (teas etc.) to kill bacteria etc., that was why they're more likely to have less genetic alcohol tolerance, because they didn't need to drink alcohol.

(I don't know if it's true though.) Tristanb 06:05, 31 Aug 2003 (UTC)

Historicaly yes. Beer was a method of treating water by fermation to make it transportable and storable. However this was what would be later called 'Small Beer', with a fractionaly low alcahol content, and is a historical use only. Any information to reflect this would be better suited to articles specificaly about beer. Alcaholic drinks, and beer as we commonly know it now is are dehydrating. (Hangovers are not an direct effect of the ethanol, but of the dehydration. Maybe this should be mentioned?). --Barberio 04:47, 15 July 2005 (UTC)

Well, I was reading "Structures of Everyday Life" (a great book btw), and it talked about beers and things. Beers used to be so common that they dcouldn't even be bought for a coin, you used up tokens for each beer, which would eventually equal the smallest coin in circulation. I was also reading somewhere that water was not a popular drink, until the Puritans got to New England, as most water sources were polluted. Beer can be 3% alcohol by volume, so I'm assuming that 30-1 ratio of water to alcohol might be enough to give you a net gain in retaining water. But, like I said, I'm interested in more information before I change the article.

~ender 2003-08-30 23:46:MST

This is going to be difficult to pin down. There are two different things being compared: [1] The concentration of alcohol in a beverage that would retard microbial growth, and [2] The concentration of alcohol in blood that suppresses anti-diuretic hormone release (most likely 0.07 - 0.09). But the concentration of alcohol in a beverage and blood alcohol level is not a simple correspondance, and depends on body weight, speed of ingestion, and many other factors. It is probably possible to drink only alcoholic beverages, never exceed a blood alcohol level of 0.6, and yet manage to take in enough fluid to supply metabolic needs. The question really is what is the strength of the evidence supporting the assertion that alcoholic beverages were the only fluid drunk by most Europeans (at any given period). Not terribly strong, I would think. It's also quite possible that something other than the alcohol concentration in the fermented beverages made them safe to drink. -- Someone else 06:56, 31 Aug 2003 (UTC)

Maybe it's not the alcohol concentration, but the fact that fermentation allows harmless yeasts, (and bacteria) to overtake and outbreed any cholera bugs.

Apparently, cheap beer in Europe used to be very dilute: it led to electrolyte depletion if you drank it to cool you off while stoking coal fires. (source: a lecturer many years ago) Tristanb

How about: It is difficult to replenish the body's fluids using only alcoholic beverages because alcohol is a diuretic, and in the more potent drinks, causes the body to lose more water than is contained in the beverage.

~ender 2003-08-31 00:32:MST

With a bit of a change, I thin: it's not the potency (i.e., concentration) of the drink that matters, it's the dose of alcohol that's consumed in a given time period. (of course, high "potency" may make this more likely, but that's not what we said before). -- Someone else 17:37, 9 Sep 2003 (EDT)

Perhaps the use of ethanol as a car fuel deserves it own page? --Jorge Stolfi

See alcohol fuel - Centrx 16:18, 29 Oct 2004 (UTC)

"A solution of 70-85% of ethanol is commonly used as a disinfectant..."

I see this figure given quite often, but unfortunately no explaination is given to why alcohol's most effective at such concentration. This is contrary to most disinfectants, which are more effective at higher concentrations; usually they are diluted because they are too toxic at higher concentrations.

Note that the standard drugstore disinfectant alcohol is 70% Isopropyl alcohol, *not* 70% ethanol. (And the Rubbing alcohol article discusses the issue of why 70%.) Nahaj 21:15, 26 June 2006 (UTC)

Hopefully someone knowlegable can answer this, if just to satisfy my personal curiosity. At my local drug stores, isopropyl alcohol are often sold in at least two different concentrations: ~70% and ~90%. Some even offer three: ~70%, ~80%, and ~90%. Somehow I feel this is a marketing ploy... - Anonymous

My guess would be that although Ethyl Alcohol is more effective at higher concentrations as a disenfectant, from personal experience, alcohol stings much more at 90% than 70%. Firestorm 01:11, Apr 5, 2005 (UTC)

You are wrong, for optimal effects there has to be water in the alcohol, 75% (by weight, not by volume!) is usually used. Cacycle 10:34, 5 Apr 2005 (UTC)

Strong claim, where are the supporting facts? (I.E. where is your information coming from?) Nahaj 21:15, 26 June 2006 (UTC)

Anyway, for an experiment in my chemistry class, we mixed ethanol and water inside a closed system (a glass tube corked at both ends). Eventually, a bubble formed in the solution, apparrently either creating a gas or losing volume. I know that no reaction occurred, so can anyone help with this problem? Most likely the water molecules are fitting inside the ethanol molecules, reducing the volume and releasing bubbles, but can anyone confirm this? Firestorm 01:11, Apr 5, 2005 (UTC)

The bubbles are from liberation of dissolved air. It is the same effect if you mix soda water and it starts bubbling (CO2 in this case). Cacycle 10:34, 5 Apr 2005 (UTC)

From basic chemistry, intermolecular forces between ethanol molecules come about largely via polar intereactions with the OH group present. Water, which is able to form hydrogen bonds (which are stronger than dipole-dipole bonds), forms stronger interactions with ethanol molecules than ethanol molecules can form with themselves. This results in the observed volume contraction, however I am unsure of the explanation for the formation of bubbles. It may be due to displacement of dissolved oxygen present in the water as a result of volume contraction. As this is from memory from first year chemistry, feel free to correct any errors I have made - Someone

Seems correct to me, the H-bonds are where its at. The ethanol displaces the dissolved air.

It must also be noted that ethanol acts as an amphiphilic compound: not only is ethanol completely miscible in water, in gasoline as well. Ethanol is not nearly as volatile as gasoline and gives off no visible smoke or soot like the latter.

[edit] Formula

OK, now the formula in the box have changed repeatedly between C₂H₆O and C₂H₅OH. It should really not be impossible to find a final solution to this. I understand that C2H60 is the "correct" scientific formula, but the vast majority who read this page will not be chemists and C2H5OH is the most well known variant and is used in the main text. If C2H6O is the variant to be used in the box, then the reason for this should be commented in the article or it will just continue to confuse readers Fornadan 22:29, 16 Apr 2005 (UTC)

This is Chemical talk. Meaning the infromation here has to be the Standart one. Not the most commonly used one, which could be liked or explained instead. NaeRey

As i understand it, the molecular and empirical formulae are C2H60, and the structural formula is CH3CH2OH. Perhaps this should be noted in the opening paragraph. (as a new wiki member i do not know how to do this, as i cant see an edit button lol) motorbyclist

[edit] ethanol more expensive than petrol

ethanol is not derived from oil. that being so a lot countries have been considering the idea of either adding or replacing gasoline with ethanol in order to decrease the amount of oil they need to produce fuels. - 210.213.230.69 03:15, 22 April 2005

This is a seperate topic under Ethanol as a fuel, altered the uses section to link there. --Barberio 23:10, 17 July 2005 (UTC)

Both C2H60 and C2H5OH are in fact correct. Personally, and in the lab, C2H5OH is more often used simply because it is more precise. However, it seems like it makes little difference to me. -SylvanScientist

[edit] Flash Point

That the Flash point is less than room temperature just doesn't sound plausible. Lee S. Svoboda 00:29, 7 September 2005 (UTC)

Look up flash point. You'll see that the flash point is the temperature that vapors will burn in air. Note that this is different than the autoignition temperature which is much higher. ~K 04:31, 7 September 2005 (UTC)

My mistake. Thanks.

Lee S. Svoboda 22:13, 7 September 2005 (UTC)

Wouldn't the flashpoint be whatever the room temperature is if it catches in the room? e.g. 18 degrees?

Strictly speaking, the flash point is the temperature at which there is enough vapor above the liquid to allow burning to be sustained. Below the flash point (17 C) you could hold a match to pure ethanol and it would not burn. Above 17 C it will burn. Walkerma 06:25, 28 September 2005 (UTC)

SR 03/03/06 The definition of flash point is: the temperature at which enough vapour will be released from the source to cause a momentary flash when a flame is applied. It's got nothing to do with the temperature at which it burns or any other of the nonsense above. I also beg to differ about the match. If you put a match into ethanol its possible to raise the temperature of that small area of the liquid to a point above the flash point which will allow the vapour to ignite and burn, when it will spread over the rest of the liquid. But if you threw a match into a beaker of it I'd agree that it'd probably just go out.

Note also that vapors may be present, but not in sufficent concentrations to actually catch fire. After all, the 'mixture' must be the correct one. Too thick and there isn't enough oxygen. Too thin, and there is not enough fuel.

Enterprisetoday 10:38, 28 September 2005 (UTC)

I've noticed that this page refers to ethanols flash point as being 17 C, yet these pages show it to be 13 C

http://66.102.7.104/search?q=cache:BZ1Y06C5LkIJ:www.biology.ualberta.ca/facilities/safety/index.php%3FPage%3D705+ethanol+flash+point&hl=en 3rd paragraph

http://en.wikipedia.org/wiki/Ethanol_fuel

under topic Other alcohols: butanol and propanol

The International Chemical Safety Card also cites the flash point as 13°C, so lets go with that (at least for pure ethanol, the flash point of ethanol– water mixtures is significantly higher). Physchim62 (talk) 12:32, 30 October 2006 (UTC)

[edit] Industrial ethanol production

Change statement. My understanding of the situation is that even with recent price hikes, most industrial ethanol is still made from petroleum.

Here are some stats.....

http://www.the-innovation-group.com/ChemProfiles/Ethanol.htm

[edit] Errors ID'd by Nature, to correct

The results of what exactly Nature suggested should be corrected is out... italicize each bullet point once you make the correction. -- user:zanimum

Para 6: It is said of the traces of benzene in purified alcohol that ‘consumption by humans lead to distinctive liver damage’. Such industrial alcohol is never drunk by humans and I think the author is confusing this with cirrhosis of the liver caused by excessive alcohol consumption over many years.
Para 9: the name of the ‘unpleasant’ agent is denatonium benzoate, better known as Bitrex.
Page 10: the term antifreeze is generally used for ethylene glycol not ethanol. Ethanol has a low melting point but this is not given.
Para 12: Ethanol is not commonly used as a disinfectant, although it has disinfectant properties.
Para 26*: Seems rather jumbled, mixing alcoholism, cirrhosis of the liver, and unproven claims that alcohol consumption is linked to various forms of cancer.

I started formulating responses to the reviewer's points here: Wikipedia:External peer review/Nature December 2005/Errors#Ethanol. --MarkSweep (call me collect) 23:00, 22 December 2005 (UTC)

[edit] Disputed

The Nature review of this article objected to the following statement:

A solution of 70% of ethanol is commonly used as a disinfectant.

The reviewer wrote:

"Para 12: Ethanol is not commonly used as a disinfectant, although it has disinfectant properties."

I guess it depends on what one considers common: I'm guesssing that in household first-aid use ethanol and propanol are fairly common. Can anyone clarify? --MarkSweep (call me collect) 22:58, 22 December 2005 (UTC)

Yes its very common in the UK, in alcohol wipes and in hand gels (which are used widely in hospitals to control infection spread). So the 70% bit is a bit wrong, but it's certainly used as a disinfectant. Editing to reflect that. Dan100 (Talk) 10:53, 23 December 2005 (UTC)

Now I've read the text I see where the reviewer is coming from: again, in the UK, solns of ethanol are not used as a disinfectant. So I've removed that bit for the time being. The article then goes on to mention wipes and rubs. Dan100 (Talk) 10:58, 23 December 2005 (UTC)

I have come across 70% ethanol used as a disinfectant: as a spray-down treatment for benchtops in a microbiological laboratory. I am not familiar with any consumer disinfectant that is simply an ethanol solution. Shimmin 12:34, 23 December 2005 (UTC)

Must say that when I was a lab tech last year we used it too, but I'd hardly say that made it "common". Worth mentioning in the article though. Dan100 (Talk) 14:05, 23 December 2005 (UTC)

Ethanol is used as a disinfectant for more than just countertops. Biological research laboratories use it as a spray down to tools and gloves and equipment before begininng any tissue culture work. 70% is a standard for research laboratories, although I have heard that solutions containing between 60-85% EtOH will work. Due to polar/non polar interactions, ethanol is a lipid solvent. It also denatures proteins. 95% ethanol is not used as a disenfectant (dehydration as opposed to disinfectant, or antiseptic).

Jawz 02:26, 15 January 2006 (UTC)

I guess it depend greatly on which country you're from. 10 years ago, it was extremly common in France household first-aid(90%, by the way. 70% is not a magic figures ;-) ) and I guess it still a very common domestic disinfectant in many "poor" country

That's right, and it's still true today: when you ask for alcohol in a pharmacy, what you get is 90% of ethanol, and it is indeed used as a disinfectant. Some other countries seem to more commonly use 70% isopropyl alcohol for that purpose. Homer Jay 14:18, 3 January 2006 (UTC)

I only just came across this recently, sorry, it's months after the discussion:

Actually the 70% figure is a sort-of magic number, although need not be adhered to exactly. It arises because many studies, dating back to at least the nineteenth century, show that 70% concentration is more effective than absolute alcohol as well as being cheaper. I don't know if the reason has been proved but it it is widely believed to be because it is almost as effective per unit time but takes much longer to evaporate.
There are many widely used household disinfectants based on ethanol, for example see http://www.cranews.com/additional_study/1996/96-11/disinfect/distab.htm#Alcohol for a list of nearly two dozen sold in various countries around the world (although a minority also incorporate propanol).
And they aren't exotic or rarely used; the product from that table, called Glen 20 in Australia, was until recently was the top selling household disinfectant aerosol in this country. (It recently got bumped into number 2 spot). It consists of 68% ethanol and nothing else but denatured water and perfumes. The exact same product is also sold in Canada and the UK by the same parent company, but under a different name (Lysol spray in Canada, sorry I don't recall the UK name off the top of my head).

To put it bluntly, the Nature reviewer's claim (that "Ethanol is not commonly used as a disinfectant") is complete balderdash. -- Securiger 07:24, 25 May 2006 (UTC)

[edit] Anti-freeze?

I've removed the following: "Ethanol is also used in antifreeze products for its low freezing point.", although Mark Sweep had added {{fact}}. AFAIK, ethanol is not used in antifreeze products. Dan100 (Talk) 10:38, 23 December 2005 (UTC)

No, antifreeze (at least in Europe) is usually ethylene glycol. Physchim62 (talk) 14:02, 23 December 2005 (UTC)
"Ethylene glycol is the most widely used automotive cooling-system antifreeze, although methanol, ethanol, isopropyl alcohol, and propylene glycol are also used." [1]. So though we're right that ethanol is used in antifreeze, I'm not sure it needs to be mentioned, as it is not a terribly important fact...that is, merely including it might be overemphasis. - Nunh-huh 00:40, 24 December 2005 (UTC)
There are other antifreezes other than that found in automobile radiators. There are antfreezes for windshield washing fluid for use in masonry (bricks can be laid in colder tempuratures) and other uses.

While this is true, the most common form of anti-freeze, the one the average person would think of, is the cooling of a car, and thus of ethylene glycol.

[edit] calories

There is no mention of the number of calories per serving. Looking around the web, I find Vodka at 220kcal/100ml at 40%ABV, which is to say ethanol would be 5.55kcal/ml. Does that sound right? Can someone find a better source? —BenFrantzDale 04:38, 3 January 2006 (UTC)

It's 7.1kcal/g [2]. also /ml is incorrect as Volume is a Vector. NaeRey

I didn't find that page when I searched. Given the listed density of ethanol, though, 7.1 kcal/g implies 5.60 kcal/ml, which is essentially exactly what I found, so at least it agrees. As for “/ml” being a vector, I don't understand what you mean. —BenFrantzDale 00:18, 23 January 2006 (UTC)

[edit] Toxicology

A reference is needed concerning the use of benzene as an entrainer during purification of ethanol above 96%. Patty's Toxicology, 5th Ed. Vol. 4., Bingham, E., Cohrssen, B., and Powell, C.H. eds. New York: John Willey & Sons, Inc., pp. 235-252, 2001 The effects of benezene by itself on health do not seem to be hepatic in nature. Perhaps benzene with ethanol has a pronounced hepatic effect.

I started a new page apart from Ethanol specifically regarding the metabolism of Ethanol in humans. It is listed at Ethanol Metabolism. The article contains substantially more information than what is presented on this page, including some molecular genetics. I did not, however, include toxicology on my sight. I would certianly be open tot he idea of incorporating my article into this page if the editors thougt that the best course of action. ATB—The preceding unsigned comment was added by Hoyabird8 (talk • contribs).

I would be in favour of moving this section to your article, giving it a {{main}} here, with a bit of explanation. --Dirk Beetstra ^{T C} 09:02, 2 September 2006 (UTC)

[edit] Ethanol

What other FOODS or food products is ethanol found in - -AND what foods would break down to ethanol in your system. I recently had an employment drug screening where they said I had "biomarkers for ETg" or alcohol consumption in my screen. I do not imbibe and am wondering if something I ate, drank or absorbed would be responsible for the results?

Highly likely, yes. More or less anything with sugars and yeast could produce something that would cause such a biomarker, without there being any alcohol involved. For instance, there is a story, hard to tell if it is true, but still a possibility, of a man in Norway who many years ago had a reaction in a police-administered blood-test. Supposedly, it came to be due to him having been at a birthday party and there eaten all sorts of breads. DannyBoy2k 17:21, 25 October 2006 (UTC)

[edit] Amphipatic Nature

I have a question, is ethanol amphipatic?

Is that a synonym for amphiphilic? If so, yes it is to a degree, but its hydrophilic nature is much stronger than its hydrophobic nature. For example you can dissolve many oils in ethanol, but if you add it to water, the ethanol almost completely dissolves into the water and leaves the oil as an unstable, very fine dispersion instead of the stabilised colloid you would expect for an amphiphilic solvent. -- Securiger 07:37, 25 May 2006 (UTC)

[edit] Vinegar

Can we get the chemical reaction for the creation of vinegar? I know it says "prepared by the action of Acetobacter bacteria on ethanol solutions," but it would be nice to know what the specific reaction is.

CH₃CH₂OH + O₂ → CH₃COOH + H₂O

The reaction for metabolizing ethanol in the human body is very similar, except that the product is acetyl-CoA rather than acetic acid. Physchim62 (talk) 04:12, 21 February 2006 (UTC)

[edit] Melting Point and Boiling Point Edits

I have reverted edits by User:71.162.62.189 (see [3] and [4]) regarding the melting point and boiling point of ethanol, as they did not provide an explanation or source for the new numbers (about 3 K lower than previous numbers) and the previous numbers (MP = 158.8 K and BP = 351.6 K) had much better agreement with the values reported by the NIST Chemistry WebBook (see [5]) of MP = 158.8±0.7 K and BP = 351.5±0.2 K. Note that I do not know the source of the previous numbers for this article. If there is reasonable evidence that the melting point and boiling point are different than the values reported in this article (158.8 K and 351.6 K), feel free to change (with explanation).--GregRM 21:54, 14 May 2006 (UTC)

[edit] Production by distillation

On The Amazing Race, some contestants made ethanol just by distilling sugar cane juice. (The Amazing Race 9#Leg 2 (Brazil)) Jobarts^-Talk 19:23, 20 June 2006 (UTC)

I saw this in the episode also (when it aired a few months ago). I think the distillation just served to separate a more pure ethanol product from a sugar cane solution which already contained ethanol. To actually generate the ethanol from the sugar cane, I think fermentation is usually used. There are a couple of newsgroup/forum threads that I found deal with the issue of fermentation in regard to this episode of The Amazing Race: See Thread on alt.tv.amazing-race and Reality Fan Forum: (see replies 153 and 167, in particular). They seem to suggest that after the teams squeezed the raw juice, the teams were provided with previously fermented juice that the teams could then distill. Unfortunately, I am unable to validate their evidence, as I can no longer easily access the episode. If anyone else has any additional information on this, I would be interested in seeing it.

As an aside, when I first saw this episode, I was curious about them using it as a fuel after they distilled it...I would expect that the resulting distillate would contain water because of the ethanol-water azeotrope. Wouldn't this cause a problem when they subsequently used it as a fuel in their vehicles?--GregRM 00:30, 21 June 2006 (UTC)

[edit] From article

Is this paragraph necessary?

Other enzyme companies such as Dyadic International have been using fungi to develop and manufacture cellulases in 150,000-liter industrial fermenters since 1994. With the advent of genetic engineering and genomics, companies like Dyadic, Genencor and Novozymes have the modern biological tools such as Dyadic's patented C1 Host Technology [6] to develop and manufacture large volumes of new and better performing enzyme mixtures to make the production of cellulosic ethanol more economical.

It reads almost like an advertisement, and it is not necessary vital to mention the names of all the companies or specific products, unless they are extremely significant developments. Comments? Tito xd^(?!?) 02:39, 2 July 2006 (UTC)

[edit] Reason for different percentages being used

No-one mentions the fact that alcohol is hygroscopic. If stored as a 95% solution, in ordinary bottles in a pharmacy, and the bottle gets opened and closed for dispensing, the atmospheric water eventually dilutes it down to what? 70% I suspect. Fact or fiction? The Nature review seems to have been a bit of a disaster? How on earth can an "expert" not be aware of the fact that alcohol is the cheapest and most readily available disinfectant used in rural clinics all over Africa? The proof is in watching what the clinic sisters actually use. But then, one does need published figures. Which should be available from central pharmaceutical warehouses. So I'll see. --Seejyb 10:02, 30 July 2006 (UTC)

The azeotropic point for Ethanol and water is nearly 96% ethanol 4% water, meaning that under normal circumstances that is as pure as it will get (it is possible to achieve higher purity levels though). Normal opening and closing of a bottle will allow some of the alcohol to evaporate off until eventually water is the dominant part of the solution, in other words 51% water 49% ethanol. I got these values straight from the CRC, and a little application of vaporization pressures. Das Nerd 18:04, 6 August 2006 (UTC)

[edit] Distinctive odor of ethanol?

As students we did class experiments on this. Statistically, the smeller could not distinguish between ethanol, methanol and isopropyl alcohol. Nor could they distinguish the breath smell of persons who had been given a glass of alcohol-free beer or ordinary alcoholic beer. The ketotic diabetic is often described as having the "odour of alcohol" (ketones). So from where the "distinctive odor"? Is there a reference? It seems to me to be a general sort of "alcohol-ish smell sensation", not distinctive of ethanol at all. --Seejyb 10:15, 30 July 2006 (UTC)

what? no way. EtOH absolutely has a distinctive odor. maybe the students in your class were not accustomed to the specific odor of alcohol solvents but it is certainly different than isoprop. and MeOH. I often work with these three chemicals (and acetone) and the difference in odor between all of them is very VERY readily detectable. --Deglr6328 19:49, 10 September 2006 (UTC)

agreed, isopropyl alcholol and ethanol are entirely different odors. Ethanol is a less pungent sweet odor where as a isopropyl (rubbing alcohol) has a much more prominent harsh pungent odor. Kyanite 06:18, 7 February 2007 (UTC)

[edit] Ethanol as a food.

Last one for today (but then I always lie): Nowhere in this aticle is alcohol mentioned as a source of energy for humans. Over at the help desk there was some discussion about the calorie value of ethanol. Dieticians write about 7kcal/g, and add that to energy intake, if one consumes alcohol. The reality and science does not support that simple conversion, but this article does not discuss the issue at all. There is certainly some divergent public opinions about this aspect, including the popular "beer belly" idea. Should these sort of facts and fancies be included in the artcle? Should the physiological effects of ethanol (e.g. fat metabolism, hormone balance) be included here? Oops, I see that is a separate article, but the reference was right at the top, not under "See also", so I've added that --Seejyb 10:33, 30 July 2006 (UTC)

[edit] Tasteless?

"enhancement of evaporative cooling inside the mouth because of its low vapor pressure). There are studies done on primates of the taste [7].--Deglr6328 19:41, 10 September 2006 (UTC)

Hi there. Keep in mind that many chemicals sold to laboratories add Bitrex to ethanol so people will be discouraged from tasting it. Make sure you are not sampling that kind when you reach your conclusion. I do now know what the answer is. -Joel Wigton

[edit] Merge anhydrous and hydrous stubs

These articles could very easily be merged with the main text. --Wtshymanski 22:23, 17 August 2006 (UTC)

[edit] Cutting down 'as a fuel'

The merge of the fuel section into ethanol fuel would need of a new, short section. What about:

Main article: ethanol fuel

The largest single use of ethanol is as a motor fuel and fuel additive. The largest national fuel ethanol industries exist in Brazil (all fuel sold in Brazil contains at least 25% ethanol).^{[citation needed]} Since production is easy (from fermentation of sugar from e.g. sugar cane) and environmentaly benign (under ideal conditions the combustion only affords water and carbon dioxide), but it has a lower energy content.^{[citation needed]}

--Dirk Beetstra ^{T C} 12:04, 19 August 2006 (UTC)

Decided to merge ethanol#as afuel into ethanol fuel after some vandalising of the section. I'm sorry I did not wait for more opinions. --Dirk Beetstra ^{T C} 20:42, 19 August 2006 (UTC)

with danger of sounding unobjective, I believe that cutting down rainforest to produce ethanol for fuel by the production of sugar cane is at the very least detrimental. Also, as I say below, the energetic efficiency of producing ethanol from starch/glucose/cellulose is nog high at all.Sikkema 21:18, 18 January 2007 (UTC)

[edit] 100% Alcohol contains benzine?

In the section that gets into absolute alcohol, it mentions a method to produce 100% alcohol by using benzine. Then it goes that the result contains small a mounts of benzine. Call me nutty, but how does 100% alcohol contain benzine? Wouldn't it then contain some percentage of benzine? Applekid 22:30, 18 December 2006 (UTC)

You're not nutty (at least not that I can tell), the 100%-claim is not correct. I changed it. Oh, by the way, it is benzene, not benzine, but that is minor. --Dirk Beetstra ^{T C} 22:34, 18 December 2006 (UTC)

Indeed, a decent Whiskey contains more benzene and e.g. polyunsaturated hydrocarbons than industrially purified ethanol. There is no such thing as 100 % pure, nowhere. Sikkema 21:13, 18 January 2007 (UTC)

The thing which is mixed up here is destilation leads only to 93% or so, but with aceotropic destillation with benzene the water is removed together with the benzene and higher concentrations than 93% can be obtained. In the end a drying with copper sulfate diethylephtalate or sodium removes the remaining tracewater. The whole has to be destilled again and you will obtain 100% alcohol, as long it is stored under nitrogen atmosphere. --Stone 15:12, 23 January 2007 (UTC)

[edit] Flammability

The physical properties section contains ethanol being flammable. Flammability is a chemical property, not a physical property.

[edit] Disinfection

Hi,

I am currently working in a cell biology lab in Münster. I found that the lab members are of different opinion concerning the disinfecting power of different dilutions of EtOH. In this article you state that 70% EtOH ist the most disinfecting - is this a study/paper you are quoting? I'd be very grateful if you could forward me the citation.

Thanks a lot,

Alexandra Kroll. —The preceding unsigned comment was added by 128.176.48.77 (talk) 15:58, 15 February 2007 (UTC).

[edit] Intent

Its quiet obvius that when eney one enters this article thay are looking for ethanol as a feul so we should make that article more obvius --J intela 04:25, 29 March 2007 (UTC)

[edit] External Links

This post discusses the scientific and end-consumer use of ethanol but not the business/investment side. One of the links I wanted to add is for an alternative energy blog, www.energyspin.com, this is not a news aggregotor, but business/investment commentary that focuses almost exclusively on ethanol in the US. Please approve this link.—The preceding unsigned comment was added by Djhyperman (talk • contribs).

See Wikipedia:External links for why a blog is most unlikely to be an acceptable external link. --Guinnog 14:46, 3 April 2007 (UTC)

"links to blogs and personal web pages, except those written by a recognized authority"

This is not a link to a personal blog, this is an investors reference which besides scientific discussion is necessary to implement any alternative energy solution. —The preceding unsigned comment was added by Djhyperman (talk • contribs).

You say it's a blog, the site says it's a blog, and all current posts are from a single person... Besides, an encyclopedic article is not a directory of websites. The link is simply inappropriate. Femto 20:10, 8 April 2007 (UTC)

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