Expert on alcahol needed

[Guest]

Is what the Americans call 'denatured alcahol' the same as our 'methylated spirits' ? and/or Can I use meth's in a two burner stove with the lablel [use alcahol fuel] on it. There is a drop or two of the original liquid fuel in the tank and it smells meth's-ish.

 

[Guest]

You are right - UK methylated spirits and N American denatured alcohol are effectively the same thing, both basically ethyl alcohol (or ethanol), which is what we drink, treated to make it undrinkable (and often poisonous) so it can be used for its non-inebriating properties (as a fuel or as a solvent) free of drinking alcohol taxes. There are many different recipes used do this, with the aim of not interfering with the ultimate use. UK methylated spirits (often shortened to "meths", and NOT to be confused with methanol [methyl alcohol], although that is what is often added) smells unpleasant and also contains a purple dye. Denatured alcohol is often colourless. The main thing you may find when using it as a fuel for cookers is that some of the added chemicals burn with an unpleasant odour . If you have this problem, try another type. If in doubt, ask a chandler for fuel for an alcohol stove.

 

[Guest]

Er... I think you may not be correct.

The word "alcohol" denotes the presence of the "OH" radical in the molecule.

Methanol (C1H3OH) and ethanol (C2H5OH) are from the alcohol family but they DO NOT have the same properties.

"Methylated spirits" is methyl alcohol (AKA methanol) with a dye added to make sure that it is easily identified. It is naturally poisonous and doesn't need anything adding to it to do severe damage to a persons central nervous system.

Ethanol is the "40% alcohol" that we see on bottles of whisky, vodka etc. It too has a toxic effect on the bodies central nervous system (i.e. you lose your sense of balance, fall over, talk funny etc) and in excessive quantities will cause illness (try projectile vomiting for starters) or death.

Both can be produced by natural fermentation or by chemical processes. (One of the biggest chemical manufacturers in the UK actually produces ethanol for a very well known brand of Vodka.)

During the USA prohibition years the backyard production of "hard liquor" often resulted in an excess of methanol in the finished product and the legendary effects of death and blindness. In other words both were produced "naturally".

As far as I am aware "denatured alcohol" is methylated spirits (methyl alcohol - methanol) with added colourants to identify that it is not in its "natural" form (i.e. colourless) and therefore methylated sprits can be substituted in its place.

Best regards )

Ian D

PS As a tip - if the bottom of your pans get black when using meths add about 5% of water to the meths before filling the container. It burns cooler but more efficiently.

 

[Guest]

Ian
I agree with your comments re methanol and ethanol. Both can be produced naturally, the former by distillation of wood, the latter by fermenation (yeast + sugars in solution under the right conditions). In both instances small quantites of other alcohols, aldehydes and ketones etc are produced as well (which gives the flavour to many alcoholic spirits). In the case of fermentation, separate distillation is necessary to produce the spirit, which again depending on conditions, can result in varying degrees of purity.

However, I beg to differ on the definition of methylated spirits. The Macmillan Encyclopedia definition is "A form of ethanol that has been made unsuitable for drinking (and is therefore duty free) by the addition of about 9.5% of methanol, about 0.5% pyridine and a methyl violet dye (as a warning that it is dangerous to drink). In this form it has many household uses, especially as a fuel for spirit burners. It is sometimes drunk by desparate alcoholics, in whom it can cause blindness and other serious medical conditions. Industrial methylated spirits (IMS) consists of ethanol with about 5% methanol and no pyradine. It is used as a solvent for varnishes, etc."

In North America, the same mixture is called denatured alcohol because "natural alcohol" (ethanol) has been rendered unnatural, but it is still effectively the same as methylated spirits, although the exact recipe might vary.

Conclusion - denatured alcohol, methylated spirits, or IMS (as well as Bacardi 151 or similar 150+ proof products) will ALL work in an alcohol burner. The latter two will be somehat more pleasant due to the absence of burning pyradine. I would NOT recommend using pure methanol in an alcohol burner because it is too volatile (although I must admit I have never tried it).

Many years ago my organic chemistry professor at university, Dr Helmkamp, was the world's expert (at the time) on this process. As a consequence we had considerable exposure to the subject. There are hundreds of recipes for making ethanol undrinkable, each with the dual purpose of avoiding taxes without interfering with the chemical properties needed for whatever the ultimate application.
Edward

 

[Guest]

Re: Expert on alcohol needed

PS to my above message -
Methanol is also known as "wood alcohol", because that was the main natural source ie wood distillation. As already stated, avoid this for alcohol burners.
Best regards Edward

 

[Guest]

Re: Expert on alcohol needed

As you said I could not use the methanol in the cooker, I put what I had in the outboard tank............... Isle of White to Poole entrance, 12 minites....... Wow......!!!

 

[Guest]

Edward

By the time I had posted the reply I got to thinking "What did the 'methylated' mean in 'methylated spirits'?" and had actually already worked out that I must be wrong.

This was on the basis that if "methyl alcohol" had been added to "spirits" (i.e. ordinary alcohol) it would be "methylated".

Goes to show what a great forum this is - I've worked with methonal, drunk copious amounts of ethanol and used methylated spirits for years and had the wrong end of the stick all this time.

It also explains why meths occasionally leaves carbon deposits (two Carbons and only one OH can result in incomplete burning).

Best regards - head hung low in shame (

Ian D

 

[Guest]

Sorry Ian, I didn't mean to be so harsh - just trying to sort out the relevant facts. As a mid-Atlantic creature (not Brit after 20 years here, no longer really Canadian, USA educated) I am so constantly dealing with transatlantic nomenclature I get confused myself. Your posting made me go back and double check my thinking. Best regards Edward