We have tests for most everything else but I dont think I have ever heard of a quick home test for methanol content in finished bio, is there one?

Fabricator,
Your timing was perfect with the question. I too am wondering how to test for residual methanol in my finished fuel.
Nick

Fab and Nick,

Currently I use a Penski-Marten closed cup tester however in absences of this we have used a small torch to see if we can ignite the fumes and of course you can take a sample and boil it for bubbles - which our indictive of methanol content.

And lastly there is always that very distinctive scent of methanol fumes which is slightly to strongly, tingly to the nose (NOT advisable as later post will tell).

I realize your looking for something a little more quantitative versus qualitative so soap doesn't really start to come out of solution until methanol contents drop below 0.25% - typically we can get to this point fairly easily - this has yielded a flash point of 93-98 deg. C approx. (Closed-cup test is a bit of technique).

But to go from here to 130 deg. C takes some heat, some vacuum and some time... And just to be safe we might even bubble all night. The soap really falls out then.

So if the soap really isn't coming out then you have to much methanol in your fuel to meet ASTM, if soap is coming readily out of solution into this stringy snot like substance then your at least at the flash point of regular diesel fuel.

Anybody got anything better?

GCG

This message has been edited. Last edited by: GCG,

quote:

Originally posted by GCG:
Fab and Nick,

Currently I use a Penski-Marten closed cup tester however in absences of this we have used a small torch to see if we can ignite the fumes and of course you can take a sample and boil it for bubbles - which our indictive of methanol content.

And lastly there is always that very distinctive scent of methanol fumes which is slightly to strongly, tingly to the nose.

I realize your looking for something a little more quantitative versus qualitative so soap doesn't really start to come out of solution until methanol contents drop below 0.25% - typically we can get to this point fairly easily - this has yielded a flash point of 93-98 deg. C approx. (Closed-cup test is a bit of technic).

But to go from here to 130 deg. C takes some heat, some vacuum and some time... And just to be safe we might even bubble all night. The soap really falls out then.

So if the soap really isn't coming out then you have to much methanol in your fuel to meet ASTM, if soap is coming readily out of solution into this stringy snot like substance then your at least at the flash point of regular diesel fuel.

Anybody got anything better?

GCG

I would never recommend to anyone "smelling for a distinctive scent of methanol fumes"

Remember if you can smell methanol then you have already passed the Threshold values. The human odour threshold is several times higher than the TLV-TWA which is 200ppm and the TLV-STEL is 250ppm. So if you can smell it then thre is already a risk to your health.


DO NOT INHALE METHANOL VAPOR!!!!

I have run several flash tests for methanol in a closed cup device and simultaneously tested a split of the same biodiesel with a weigh-heat-weigh technique.

My numbers show when the closed cup flash point reaches about 130 deg C then the weigh-heat-weigh result shows about 0.15% to 0.2% methanol was present in the biodiesel at the start of the closed cup test.

Please note, I was looking more at "trends" on my samples with my equipment rather than absolute accuracy and precision as would be practiced by a reference laboratory.

In other tests I have taken a small amount, about 1 liter at a time, of unwashed biodiesel that met the 3/27 test and then vacuum de-methed the biodiesel until the soap settled out. These tests were done in lab' glassware and it was quite easy to see the dramatic soap drop out. The biodiesel was tested in the closed cup device for flash point after the soap dropped out. The flash points of several tests were well in excess of 130 deg C. They generally registered at or above about 170 deg C.

By extrapolation, my results suggest that soap will freely drop out of any demeth'd biodiesel samples that show a starting methanol concentration of about 0.1% up to 0.15% using a weigh-heat-weigh test.

All soaps are/were sodium based.

I don't know if this would work in biodiesel or not.

From:
CHEMICAL SOLUTIONS
Reagents Useful to the
Chemist, Biologist, and Bacteriologist
By
FRANK WELCHER
Assistant Professor of Chemistry
Indiana University
1942

AGTTLHON'S REAGENT

Use: Test reagent for reducing substances.
Preparation: Dissolve 0.5 g. of potassium dichromate in 100 ml of nitric acid (sp. gr. 1.33).
Remarks: Reagent gives a blue-violet color (changes to green when heated) with easily oxidized substances: e.g., alcohols, aldehydes, glycerol, carbohydrates, etc.

Is nitric acid a good idea?

Ken

Alllllrighty then.........umm, I was looking more for something like "Just dip these little strips in it and". I'm just a simple tin bender, I dont even know anybody who passed chemistry in high school.

High school?? I know about drop out. Expert status. With all this talk about drop out, I feel right at home.

That's what I'm sayin brother.

Producer,

What scales are you using to get that kind of precision? Did you account for water?

quote:

Originally posted by RickDaTech:
What scales are you using to get that kind of precision? Did you account for water?

Hi Rick.

My scale is a Fischer Scientific electronic scale with an accuracy of 0.1 gram.

I made no special adjustment for water. If there was some water present, and if some of that water evaporated while driving off the methanol, then the weight of that water would have been a part of the heat-weigh-heat (HTH) calculation.

The amount of any water that may have been present was probably negligible. Dry TGs were used and 30% CH3Na-O catalyst in methanol was used as the catalyst.

My HTH set up consisted of a glass beaker, portable electric thermometer with probe and lead, teflon stir bar, and tape. The probe was taped to the inside of the beaker and the stir bar was placed in the beaker. The tare weight of the beaker, tape, bar, and electric thermometer was determined by placing the entire assembly on the scale.

Biodiesel was then added to the beaker and a gross weight was obtained. Then the beaker, et. al. was placed on the stirring hot plate. The temperature was slowly brought up to about 90 deg C. The beaker with its biodiesel and "attachments" was transfered back to the scale and weighed about every 30 minutes. The weights were recorded. When no weight loss was observed through two weighings, then the methanol was "assumed" to have been evaporated.

The system allowed taking weight measurements without having to pull small samples from the beaker. Weighing the entire sample eliminated the problem of taking small samples in small containers and running the risk of leaving traces of the material on the inside of the containers. This arrangement eliminated a lot of potential sources of error.

There are scads of cheap breath-alcohol breathalyzers on ebay. Don't know how much I trust the readings to go driving, but it should be a very sensitive tester for methnol vapors. I had one for a while, and it would certainly respond to methanol vapors below my threshold of detection.
It died when left in a box with a bottle of H2SO4 solution. I didn't get to do a more scientific exploration of the sensitivity relating to methanol content in bd.
I know there is a large scaling factor in the displayed measurement since, e.g. a .08% BAC, will result in a much lower exhaled-air-alcohol-concentration.

Now that is interesting, I have access to a brethalizer, hmmmmmm.

quote:

Remember if you can smell methanol then you have already passed the Threshold values. The human odour threshold is several times higher than the TLV-TWA which is 200ppm and the TLV-STEL is 250ppm.

But TLV-TWA is for 8hrs continuous and TLV-STEL is for 15minutes continuous...were talking about a 3 second sniff.

You need to be careful with methanol...but don't need to freak out about it.

By the Ryan Butt-Dyno for methanol exposure;

If it burns your nose: leave right now and have some booze later.

If you can smell it: don't stay longer than 5 minutes, and have some booze later.

If you can't smell anything, but you get a headache after 15 minutes: leave now and have some booze right away.

If you never did smell anything, and you don't ever get a headache later, and you're sure you didn't get any exposure at all: have some booze...better safe than sorry!

The very last step in any biodiesel procedure is "Have some booze." It'll keep you safe!

Ryan P,

AMEN

And have a drink on me..

GCG

quote:

Originally posted by Ryan P.:

quote:

Remember if you can smell methanol then you have already passed the Threshold values. The human odour threshold is several times higher than the TLV-TWA which is 200ppm and the TLV-STEL is 250ppm.

But TLV-TWA is for 8hrs continuous and TLV-STEL is for 15minutes continuous...were talking about a 3 second sniff.

You need to be careful with methanol...but don't need to freak out about it.

By the Ryan Butt-Dyno for methanol exposure;

If it burns your nose: leave right now and have some booze later.

If you can smell it: don't stay longer than 5 minutes, and have some booze later.

If you can't smell anything, but you get a headache after 15 minutes: leave now and have some booze right away.

If you never did smell anything, and you don't ever get a headache later, and you're sure you didn't get any exposure at all: have some booze...better safe than sorry!

The very last step in any biodiesel procedure is "Have some booze." It'll keep you safe!

Ryan P.
No one is freaking out, however you do appear to have a problem with either reading or comprehension. Maybe you have been exposed to too much methanol because you don't understand or appreciate the risks. Or quite simply because you don't want to.

I suggest you and GCG re-read what I wrote "the human odour threshold is SEVERAL TIMES HIGHER than the TLV-TWA"

So as you rightly pointed out the TLV-STEL is 15 minutes at 250ppm that means it is safe to be exposed for up to 15 minutes to 250 ppm of methanol however if you can smell methanol then you have been exposed to a much higher amount than 250ppm. SERVERAL TIMES 200 is a lot more than 250ppm.

Now I doubt it is a linear relationship between the TWA and the STEL but an increase of only 50ppm (25%) (from 200 to 250)is sufficient to reduce the allowable exposure time from 8 hours to only 15 minutes therefore it is safe to assume there must be a substantial reduction in safe exposure time if you can actually smell the stuff. (Where in the hell do you get that it is safe to spend 5 minutes if you can smell it, please post the research that backs that up, I would love to see it.)

So a couple of "sniffs" looking for methanol, especially if it is there in any reasonable quantity may well be sufficient to cause permanent damage no matter how much alcohol you drink.

So I stand by my previous post and also suggest that anyone who advocates that smelling a sample as a suitable test for methanol is either totally ignorant of the risks, does not care about what others, especially newbies, read and or a complete arrogant arse who doesn't really care about anything or anyone.

Personally, I think it's better to be paranoid about methanol vapors than to be too relaxed about them, which is something that seems to happen to a lot of biodiesel brewers over time. With methanol, just because you're paranoid certainly doesn't mean it's not out to get you!

Might be of interest...
http://www.inchem.org/documents/hsg/hsg/v105hsg.htm

Good link.

Here's what I see as most important (with some highlighting added by me):

quote:

Although oral ingestion is the most frequent route of poisoning, in severe and exceptional conditions inhalation of methanol vapour and percutaneous absorption of methanolic liquids are also effective in producing acute toxic syndrome characterized by metabolic acidosis, central nervous system depression, blindness, coma and death.

The severity of the metabolic acidosis is variable and may not correlate well with the amount of methanol ingested. The variability of the toxic dose is a prominent feature in methanol toxicity.

The symptoms of methanol poisoning, which may not appear for 12 to 24 h, include visual disturbances, nausea, abdominal and muscle pain, dizziness, weakness and disturbances of consciousness ranging from coma to clonic seizures.

And from the Conclusions:

quote:

Methanol occurs naturally and is present in the diet. It can be absorbed rapidly by the inhalation, oral and dermal routes and distributed in the body, but it is only slowly metabolized to formate (which is believed to be the cause of visual damage) and then excreted. Methanol is rapidly degraded in the environment with no evidence of bioaccumulation. The available data do not indicate that there are any significant effects in the environment.

What have I learned:
It takes a severe and exceptional situation to inhale enough methanol vapor to cause health effects.

Since the severity is so variable person to person, and does not correlate to exposure, what effects you may not effect me, and vice versa.

It is absorbed rapidly by inhalation, but is broken down to the toxic elements very slowly and is more likely to be passed (especially when the enzymes are competitively saturated breaking down ethanol ).

It breaks down so fast in the environment as to be a non-issue for anything but a major release, which is defined as over 25L from this document.

Fuzznag,

You are correct, I shouldn't have said, sniffing biodiesel for detection of methanol is an advisable method. Especially considering the huge number of new members. A person should always be responsible for the listening of the audience.

As to my "amen" comment, I was just having fun especially since the previous issue of SmarterBiodiesel had an entire article devoted to methanol exposure and ethanol doping/blocking. It was a fun and informative read.

Methanol is no joke and handlers should take it seriously and probably more seriously than many including myself practice. 150 ml will kill you if injested, it is readily absorbed through the skin, it is a breeding ground for bacteria, its first sign of over exposure is degrading eye sight and the list goes on!

On the flip side of this though, if your making biodiesel and your using methanol to do it - I find it highly unlikely that the homebrewer will get all the methanol out of the biodiesel every time.

And considering our keen sense of smell it is also highly likely the homebrewer, whether trying to or not will learn the smell of methanol. If by chance this is the case, then obviously it still needs to be demethed.

I am by no means condonning this as an actual method of determining methanol content, just that, its scent would be an indicator that further removal was necessary.

This is however obvious and probably not worth mentioning in the first place...


I think I need a beer! What kind of good brew do they have there in Yorkshire?
GCG