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doctor demo
07-04-2008, 11:34 PM
Hi all, I have Googled and Wickpedia-ed and can not find what I'm looking for.
What I am trying to do is make sure there isn't any water in My partial drums of methanol befor combining contents to get one full drum and return emptys for deposit.
I have been told that moisture in the air over time can add up to a significant amount of water in the alky . Not good for parts or performance.
I have read about distilling it with heat in a closed vessel and vacuum so the water is left behind, but then the article goes on to say be carefull as you can't tell water from methanol. So if you ''boil '' off the alky from the water in a vacuum and recover the vapor it will condense back to alky, so if you stay below 200F. there shouldn't be any water . Right?

Seems like there should be an easier way.
Steve

Evan
07-05-2008, 12:17 AM
It isn't that simple. Have a look for information on making your own alcohol fuel. I'm sure it is a popular hobby these days.

torker
07-05-2008, 12:26 AM
Steve.. I have a brand new drum of Methanol I've been trying to sell or give away or whatever. Problem is I was the only guy to run blown alky around here.
There does seem to be a shelf life for that stuff.
I always kept my barrels in a temperature controlled shed and used them up quick... a 572/14-71 will do that :D
If I ever had a part barrel left over I'd pour the remains into plastic jerry cans. Never had a problem with it that way. I'm wondering about this barrel.. it's had to sit outside for a year now.
Russ

doctor demo
07-05-2008, 01:12 AM
Steve.. I have a brand new drum of Methanol I've been trying to sell or give away or whatever.
There does seem to be a shelf life for that stuff.
I used them up quick... a 572/14-71 will do that :D
If I ever had a part barrel left over I'd pour the remains into plastic jerry cans. I'm wondering about this barrel.. it's had to sit outside for a year now.
Russ
Russ, I would come and get it but we are to far apart.
A 525 injected drinks it's share too.
Russ why don't you mix it with your gas? 10-15% , you will offset the high cost of gas and use up the alky. Kill two birds with one stone so to speak.
Nuff bout u now back to ME.
Steve

ckelloug
07-05-2008, 01:37 AM
Unfortunately with alcohol and water, during simple distillation, an azeotrope is formed. This is a mixture of the water and the alcohol that cannot be separated further by ordinary distillation. I checked the Wikipedia entry on distillation as I couldn't remember the term azeotrope. I don't know what the percentages of methanol and water are in the azeotrope. Wikipedia article on distiilation says 95% for ethanol and water.

See http://en.wikipedia.org/wiki/Distillation

Alternately, if you can stand some waste, distilling with a temperature less than the boiling point of water will give you almost pure alcohol until the alcohol concentration gets to the point where the azeotrope forms.


To determine the composition, one thing to try would be to measure the density. You'd need an accurate scale and graduated cylinder however. Density of methanol and density of water should be lookupable trivially.

I think doctor demo's idea is great however adding it to the gas in your normal car. Methanol is a major component in the stuff for getting water out of your fuel system anyway.

Best of Luck,

Cameron

Evan
07-05-2008, 02:14 AM
Methanol is also corrosive to steel. I wouldn't put it in my regular vehicle unless it is certified ok to use methanol.


To determine the composition, one thing to try would be to measure the density. You'd need an accurate scale and graduated cylinder however. Density of methanol and density of water should be lookupable trivially.

Do like they do in a lab and dilute it precisely. Then you can use a wine densiometer that floats in the mixture and correct for the difference between methyl and ethyl. For instance, if you take what is nearly pure alcohol in 1 part (an aliquot) and mix it with 9 parts of water then a 90 percent mixture becomes a 9 percent mixture and you can measure it as if it were wine.

oldtiffie
07-05-2008, 02:31 AM
Methanol is also corrosive to steel. I wouldn't put it in my regular vehicle unless it is certified ok to use methanol.
.

And that isn't all. The whole fuel system needs to be OK - tubing, seals, "rubber", carby (if you have one), injection system.

There was quite a "push" here in OZ about 10% blend. Most modern cars are or seem to be OK. Older cars a more "suspect".

Others in OZ will be more au fait with this than I am.

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

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

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

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

http://www.racv.com.au/wps/wcm/connect/Internet/Other/Search?query=ethanol&submit.x=25&submit.y=11

steverice
07-05-2008, 02:33 AM
You need to check the specific gravity with a hydrometer. at 60 degrees farenheit, it should be .792.

If methanol sits around, or is left open it will absorb the humidity from the atmosphere. If you open a jug and plan to reseal it fo any lenght of time you need to purge the atmosphere from the container. I have used Nitrogen in the past.

doctor demo
07-05-2008, 04:03 AM
Unfortunately with alcohol and water, during simple distillation, an azeotrope is formed. This cannot be separated further by ordinary distillation.

Alternately, if you can stand some waste, distilling with a temperature less than the boiling point of water will give you almost pure alcohol until the alcohol concentration gets to the point where the azeotrope forms.



Best of Luck,

Cameron
I would certainly be up for some waste instead of all waste.My thought process was to ''boil'' heat the methanol to it's vaporization point wich is below the water's boiling point then through a cooler to a holding tank all under vacuum.
Thanks Cameron
Steve

doctor demo
07-05-2008, 04:27 AM
You need to check the specific gravity with a hydrometer. at 60 degrees farenheit, it should be .792.

If methanol sits around, or is left open it will absorb the humidity from the atmosphere. If you open a jug and plan to reseal it fo any lenght of time you need to purge the atmosphere from the container. I have used Nitrogen in the past.
You know you can go through life and have something right under your nose and not even give it a thought untill someone else brings it up and then the feeling of stupidity sets in.:)
I have nitrogen, and not only purge the drum, I could use it to ''pump'' the methanol from the drum instead of that stupid plastic hand pump and would never have to open a bung for a vent keeping air out alltogether.:D .
I don't have the hydrometer,cylinder or thermometer set any more I gave it away years ago.
Thanks for the info,
Steve

jacampb2
07-05-2008, 05:09 AM
A 55 gallon drum is NOT a pressure vessel. You would be advised to not pressurize the drum to transfer the MeOh. Most heavy duty drums with the clamp ring retained lid will only hold to about 7-8 psi and aren't really even intended for that. The stamped and rolled steel barrels can and will fail below 5 psi. We had a safety presentation at work a few years ago, a couple of guys at an overseas chemical plant were transferring liquid from a drum under pressure, and the drum exploded killing at least one of the two. The normal procedure was 5psi if I recall. After that there was a big safety initiative to make sure this was not a normal operating procedure anywhere in our plant.

As for stripping the MeOh from the H20, keep in mind that the boiling points are going to shift quite a ways when under vacuum. You need to be able to maintain a constant vacuum, and constant temperature to do this right. I think I would consider buying a few pounds of desiccant beads and dropping them in the barrel before I went to the trouble of trying to set up a distillation column.

Later,
Jason

oldtiffie
07-05-2008, 07:11 AM
Is this really worth the worry and the risk?

If it goes wrong in any way I'd guess your wife, neighbours, insurance company and the law are not going to take too kindly to it. The only ones pleased may be the local press/media - if it fills a gap in a "slow day".

Why not just take it a local disposal centre or get a Contractor to dispose of it?

tryp
07-05-2008, 07:23 AM
Distillation is one method of removing water from alcohol, on the plus side methanol doesnt form an azeotrope with water, so distillation is fine if you have a fractionating column and an appropriate distilling apparatus. Jury rigging something is not something I'd do with a flammable and toxic solvent. On the down side for distillation is the time and energy cost.

Another method that will bring you down to dry again is using a drying agent and filtration or decantation. Calcium oxide is my drying agent of choice for alcohols.

Vacuum distillation of such a low boiling system would be most likely frustrating unless you have a very good way of regulating the vacuum to a very low value. Have you ever seen an entire flask flash over into a reciever because of too much vacuum? Very easy to do with methanol at room temperature. and you would need a chilled reciever and a fractionating column.

Not knowing what you are using the methanol for though and we cant suggest something that is best. Maybe you could use a drying agent, decant and filter and then bulk distill(no need for a frac column) to remove the trace of solids.

Duffy
07-05-2008, 01:05 PM
Where do you suppose a person could buy calcium oxide, AKA unslaked lime today. I do not think the bricks and mortar folks even know what it is anymore. As an "off the wall" suggestion, buy a pound or two of silica gel, put it in a net bag and drop it in the methanol. If it changes colour, there was water and it is now in the silica gel. Dry the gel in an oven at "the recommended temperature," (I forget what that is- about 300F?) and try it again. If it changes colour AGAIN, repeat the process until it doesnt. Silica gel is comparatively cheap, available- (craft shops for drying flowers,) and absorbing water from stuff is what it does. Duffy

ckelloug
07-05-2008, 01:14 PM
Hi tryp,

It sounds like you have some experience with this. Are you a chemist by chance? Thanks for the response about the azeotrope not forming with methanol. I just assumed one would from because it does with ethanol and I didn't look it up. Bad assumption apparently.

For the OP,
You could always build a steam engine with a methanol fueled lamp as a heat source :) Should use up the alcohol in about 10000 years for the average local value of "steam engine".

Regards all,

Cameron

tryp
07-05-2008, 02:41 PM
Well I've got three years of university chemistry(and 2 years of engineering) but most of my chemistry education is from personal study previous to during and after that. I have a personal collection of ground jointware that is rather large, I havent used it in a long time, but I cant imagine getting rid of it.

As far as quicklime yes I understand how difficult it is to get, it is in the top three chemicals produced in the world tonnage wise but I recently had to source half a ton for some piloting work. Let me tell you, more than 10kgs and less than a railcar full is pretty much impossible to secure at any price, from any supplier. After a week of searching I found a good supplier, lead time 1 month?????

But if you just need a kilo, its easy to get from a pharmacist or pretty much any fine chemical supplier. I've heard it can be had at masonry supplies, hardware and farm stores, and it should be but I've never had any luck, only hydrated lime from them.

doctor demo
07-05-2008, 07:43 PM
A 55 gallon drum is NOT a pressure vessel. You would be advised to not pressurize the drum to transfer the MeOh. one of the two. The normal procedure was 5psi if I recall. After that there was a big safety initiative to make sure this was not a normal operating procedure anywhere in our plant.

I would consider buying a few pounds of desiccant beads and dropping them in the barrel before I went to the trouble of trying to set up a distillation column.

Later,
Jason
Good point Jason,
I know that a drum is not a pressure vessel, and the lid is a very large flat diafram and wouldn't take much to remove it.:eek: .
I was thinking along the lines of 1/2 to 3/4 psi for transfering from the drum into 5 gal plastic jugs. Right now we use a pos plastic siphon pump but you have to have a vent open for it to operate drawing in air and humidity.
Distilation sounded simple enough on the surface, I mean how can all those moon shiners be wrong? But I think I'll save the distillation tower for another project and give the silica gell some more thought.

I sincerely thank all who responded to this thread so far, I don't plan to dump any methanol nor do I plan to pay to dispose of it . My intentions are to save as much of the methanol from the partial drums and then to keep future drums free of water.

Steve

Evan
07-05-2008, 11:22 PM
Tryp,

Next time you need some calcium oxide in a hurry check with any place that sells industrial water softening supplies. They have it.

Jim Caudill
07-05-2008, 11:32 PM
Sell it to your local Self-Serve car wash (assuming that it gets below freezing). They don't care if it has a little moisture, after all they use it with their foaming brush product to keep it from freezing.

J Tiers
07-06-2008, 02:06 AM
Azeotrope, heliotrope........ whatever....

is not the real issue that you have an equilibrium issue and the partial pressures of water vapor and alky vapor are ruling the results?

Certainly, if the mix you have is still burnable, it is not smart to pay to dispose of it. Check the contents on a can of 'Heet", if you can still find one. A number of those gas line de-icers did have methanol, or in some cases ispropanol, as their active ingredient.

If you toss a bit in each tankful, you may have a benefit, and almost surely will not have a problem, and it will pay you, instead of you paying for it.

I am assuming, for the benefit of those who haven't "got it" as to what you have, that this is racing fuel that has been sitting long enough to be suspect......

torker
07-06-2008, 02:14 AM
I am assuming, for the benefit of those who haven't "got it" as to what you have, that this is racing fuel that has been sitting long enough to be suspect......
Yup.. a few missed that. I know exactly how corossive alky can be on a fuel sysem.
I've blown out and "oiled" fuel lines/fuel pumps after races for years.

Evan
07-06-2008, 02:38 AM
It isn't a good idea to use in in your vehicle, even in small quantities. The major problem with methanol and water is that when methanol that has water mixed in is then mixed with gasoline the water comes out of solution and stays in the gasoline. So, even if small amounts are used per tankful water will accumulate in the gas tank if the methanol contains water.

J Tiers
07-06-2008, 10:45 AM
It isn't a good idea to use in in your vehicle, even in small quantities. The major problem with methanol and water is that when methanol that has water mixed in is then mixed with gasoline the water comes out of solution and stays in the gasoline. So, even if small amounts are used per tankful water will accumulate in the gas tank if the methanol contains water.

If the gasoline in BC has any ethanol, which it may not, that won't be an issue. In the US it would be pretty much a non- issue with most gasoline.

And, if that is so, why has the methanol been used as a gas 'drier"? I am pretty certain that it has been.

I could make the experiment if I could find any non-ethanol-containing gasoline here.

doctor demo
07-06-2008, 03:30 PM
, The major problem with methanol and water is that when methanol that has water mixed in is then mixed with gasoline the water comes out of solution and stays in the gasoline.water will accumulate in the gas tank if the methanol contains water.

So Evan, if I dump 20 gal. of methanol in 5 gal of gas would I then be able to draw the water out from the bottom of the tank? Or does the ratio have to be closer?
Steve

Evan
07-06-2008, 04:50 PM
And, if that is so, why has the methanol been used as a gas 'drier"?

Anhydrous methanol will take a small amount of water and keep it in solution when mixed with gasoline, or it will pick up that amount from the tank. However, it isn't nearly as much as isoprop or ethanol. If the methanol being added to the gas already has water in it that exceeds the amount methanol can carry when in solution in gasoline then that excess water drops out of solution. Methanol by itself will absorb much more water from the atmosphere than it can hold when in solution with gasoline.

J Tiers
07-06-2008, 04:57 PM
Since he is in the US, and there is ethanol in just about all our gas, he should be OK........ and in any case, it wouldn't be much, and this is summer.

tryp
07-06-2008, 06:51 PM
Tryp,

Next time you need some calcium oxide in a hurry check with any place that sells industrial water softening supplies. They have it.

Very good to know Evan, thanks!