Denatured Alcohol

Thanks

Steve Kubien

>Thanks for the link. I appreciate the help. Will you be at Darrell's BBQ in August? Did we meet at the his Christmas shindig?

Steve Kubien

Ajax, Ontario

remove the _9 to email

Chemistry lesson... *LINK*

Scott in Douglassville, PA

>I believe you are incorrect. "Methyl Hydrate" (at least in Canada) refers to methanol or wood alcohol. Follow the link below and scroll down to Methyl Hydrate. I believe this product is CH4O.

Hi, Craig -

William's correct on this one. I'll hit some highlights for you, trying to avoid straying too deeply into the actual chemistry:

• The formula for methanol, CH₃OH, is conventional and suggests a rudimentary structure, namely that there's a carbon with three hydrogens at one end, and an OH at the other. The "CH₃" is a methyl- group; the attached "OH" is what makes it (in this case) an alcohol. The formula you referenced, "CH4O", is (in this case) an archaic written convention, summing the number of hydrogens together.



• Methanol is one of those compounds that've been around long enough to accumulate a ton of common, archaic, or otherwise colloquial names. "Methyl hydrate" and methanol are the same thing. Might see it written as "Methyl hydroxide" as well. All the same stuff.



• Methanol is toxic. It's an obvious denaturant, used to make otherwise potable alcohols toxic. This reduces the cost (by minimizing taxation), and probably helped keep earlier labs stocked with necessary reagents. Coincidentally, I've worked at more than one lab where transient techs (subject to frequent workplace attrition) would snarf up some of the "100%" ethanol for their weekend exploits.



• Methanol is toxic by ingestion, inhalation, and absorption. Ingestion is the obvious high-toxicity route; inhalation will cause some drunkenness-like effects if the concentration is high enough. Contact will dry skin quickly, and cause some significant dermatitis if the contact is often enough. It's dangerous stuff, and should be used carefully. Which is why only a few percent is necessary to denature ethanol.

I worked with methanol for years. A few times, I used it for an hour or so without adequate ventilation (read: outside a vent hood). Aside from creating a real fire hazard, I got light-headed enough to require moving to open air. Again, it's surprisingly nasty.

I'm not picking on you here; there's a lot of conjecture and hearsay about alcohols and solvents 'round here on occasion, and I'm just trying to scatter some info about.


Methanol MSDS

Re: Chemistry lesson...

Craig Treleaven

>Hi Scott:

I appreciate the information. I had previously thought that methyl hydrate in Canada must be different from what people in the U.S. were referring to because they would always disclaim about how dangerous it is. That didn't line with the product that we buy here off the shelf and that has moderate safety warnings on the label. Thanks for clearing that up.

We all agree that ingestion and inhalation of mehyl hydrate is bad. William wrote that methyl hydrate "is a lot more dangerous and poisonous than either isopropanol, C3H7OH, or ethanol, C2H5OH." Strictly speaking that is true since you can wash with the former and drink the latter!

Now, I don't want to talk anybody into using anything that they are not comfortable with, but methyl hydrate does not seem, to me, to be an unmanagable risk. The MSDS from my supplier includes the following section:

Potential Acute Health Effects

Extremely hazardous in case of ingestion. Hazardous in case of inhalation. Slightly hazardous in case of skin contact (irritant, permeator), of eye contact (irritant). Non-sensitizer for skin. Severe over-exposure can result in death.

Obviously, it is not benign. Laquer thinner and paint stripper, however, seem to be another level higher in risk and more than a few of us have them around and use them. My point was, that with proper handling, it makes a good solvent for shellac and is inexpensive to boot. Another option for those who might be so inclined.

Craig

PS I wish I could link to the Recochem MSDS but one has fill out a form to be permitted access to that data.