Methanol vs Ethanol

Discussion in 'Open Forum' started by Dan D, Dec 16, 2011.

  1. Dan D

    Dan D Subscriber

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    Recently I went to my hardware store looking for some muriatic acid (HCl, spirits of salt). They only had what was called "green" muriatic acid, so not being sure exactly what this was (the label claimed it had "90% lower fumes than standard Muriatic Acid and is safer to use and store", so I decided to pass.

    On the shelf I also noticed that they had "green" denatured alcohol (meths) as well as the "regular" stuff.
    This piqued my curiosity, so when I got home I looked up the difference in the manufacturer's MSDS data.

    The regular alcohol was 50% methanol & 50% ethanol and the "green" alcohol was 90% ethanol and 10% methanol. They claim its "green" because it has (and I quote) "twice the renewable resources as our regular Denatured Alcohol. It is better for the environment because it is biodegradable. It contains no ozone depleting chemicals." Ethanol is made from plant material and methanol from natural gas (in the US), so I guess that's what they mean.
    Anyway, a bit more research determined that ethanol has a higher heat of combustion than methanol. Not by a lot, (~22%) but when you are trying to heat up a big heater or projector burner, hotter is probably better. I'm going to try some after I finish the gallon of regular alcohol I have.

    At the end of the day it's probably a distinction without a difference; what do you think?

    Dan
     
  2. David Shouksmith

    David Shouksmith United Kingdom Founder Member

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    I'm cynical enough to believe that the word 'green', like 'organic', is usually no more than a marketing term designed to attract the gullible and thus increase profits.

    I'm very surprised to see that the US is apparently still using the names 'muriatic acid' and 'spirit of salt'. I think more-or-less the rest of the world abandoned their use in 1921 and henceforth used the IUPAC system of naming chemical substances...
     
  3. Nils Stephenson

    Nils Stephenson Founder Member

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    The standard stuff I buy here in Denmark is 93% ethanol. It's available at most supermarkets and hardware stores. Never had a problem with it.
     
  4. Bob M

    Bob M R.I.P.

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    Methanol(wood alcohol) is getting harder to find in let's say gallon cans. I know guys that use it for racing fuel and buy it by the 55 gallon drum. Most paint stores carry "denatured" alcohol because it's cheaper and with the degree of ethanol production in the USA it's more readily available. According to Wikipedia other additives include isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, and denatonium.
    All these just to make it unsafe to drink. HUH? :doh:

    Bob
     
  5. 350i

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    This is post is especially interesting to me, when I get my alchohol lantern running I'll be using both methanol and ethanol (95%).The methanol is generally cheaper here in the UK because there's no duty to pay on it.
    I've worked in Sciences for a good few years now and use HCl a lot, but I've never heard it called either of those two names before. You learn something new every day...
    Cheers
    Trevor
     

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