George,

Good question. I am reluctant to answer because... This is theory, not supported by research yet.

I theorize that runnier oil (triglycerides or TG) are more soluable in methanol than thicker more saturated ones with higher gel points.

It is important to realize how 3/27 works. TG is partly soluable in methanol. But, not very soluable, so if there is any reasonable amount, some of it will fall out. That is what we look for. Apparently, TG is more soluable in methanol at higher temps.

It may be that more saturated TG is less soluable than unsaturated TG. At the vary least, don't have data to say there is no difference.

That is why I think it would be important to have consitant feedstock, if you want to use forced fail to compare batches. If not, you have another variable which could explain the difference in result.

Andrew

Hello Andrew

quote:

Originally posted by Andrew Morris:
George,
Good question. I am reluctant to answer because... This is theory, not supported by research yet.
I theorize that runnier oil (triglycerides or TG) are more soluable in methanol than thicker more saturated ones with higher gel points...
Andrew

All the oils used in making biodiesel are triglycerides. Being a triglyceride has nothing to do with "Runnier" or more saturated with higher gel points.
An interesting idea. I have never performed any viscosity tests that shows at 50deg C Palm oil to be "Thicker"/a higher viscosity than Canola oil. Have you?

Tilly,

quote:

All the oils used in making biodiesel are triglycerides. Being a triglyceride has nothing to do with "Runnier" or more saturated with higher gel points.
An interesting idea. I have never performed any viscosity tests that shows at 50deg C Palm oil to be "Thicker"/a higher viscosity than Canola oil. Have you?

I observe that it is thicker. It pours more slowly at the same temp. Nothing quantitative to report.

About the other parts, said it is a theory. I will let you know when I have data.

Andrew

Hello Andrew

quote:

Originally posted by Andrew Morris:
Tilly,
I observe that it is thicker.

At what temperature did you make this observation. What might be true at 0deg C Might not be true at 40deg C.

quote:

It pours more slowly at the same temp.

Describe "More Slowly" Do you mean Palm oil's terminal velocity is less than Canola Oil's terminal velocity Or are you refering to the viscosity of the oil?

quote:

Nothing quantitative to report.

Does this mean you have never really made any tests to confirm your statement. That does not surprise me.

quote:

About the other parts, said it is a theory. I will let you know when I have data.
Andrew

I can wait.

Tilly,

Sorry... You are still too argumentative for my taste.

Please ignore my posts. Don't ask me questions. I won't answer anyway.

Andrew

too good to be true but true a simple test with quick results better than the double water test is this the reverse of the titration test to determine amount of catalyst amd does anybody have more info on: organic (ethyl esters) bio-d and how does the tumeric work in the ph testing? Thx for the support

Hello Pable
Titrationis different than this test.
This test detects Triglycerides in the biodiesel.
If there are minimal triglycerides in the biodiesel nothing will fall out. This is an indication of very high conversion biodiesel.
I personally doubt that anyone will ever be able to determine whether the biodiesel is actually ASTM conversion using this test but for 5 cents a test, it certainly beats the next best backyard test as far as speed and simplicity goes.

Bump

This thread should be a stickey

Thanks for the 'Bump'. Lately I have produced a couple of 110L batches of BD utilizing an 18% MeOH mix that has passed the 3/27 test. With this last batch I stuffed an extra 3 cc of finished product in without identified fall-out. Just an observation. Comments?

Hello fatkid

Several people are reporting passing the Warnqvest using less than 20% methanol in a single stage.
Without GC testing one can not be sure whether it is ASTM or not. I suspect that Your diesel engine will not know either.

quote:

Several people are reporting passing the Warnqvest using less than 20% methanol in a single stage.
Without GC testing one can not be sure whether it is ASTM or not. I suspect that Your diesel engine will not know either.

This is exactly what is wrong with the 3/27 test. It is too small of a proportion. It will probably take 0.10ml of dropout for you to clearly see. That means your fuel has to be out of conversion by a lot before you see it. And there is speculation that mono and dyglycerides are more soluable in methanol. That means you need triglycerides to fail the test and that is highly unlikely to happen unless you make a really bad batch.

This test should be done as first designed 25/225. Or for even a better chance of getting it right use this test as 100/900. You are not wasting any methanol. The methanol should be kept in a seperate container so you know that 10% of it is biodiesel and you need to use an extra 10%, when making biodiesel. It will make the same quality biodiesel as pure methanol. It might even make better biodiesel because the biodiesel will work as a cosolvent.

Logan Vilas

quote:

Originally posted by Logan Vilas:
The methanol should be kept in a seperate container so you know that 10% of it is biodiesel and you need to use an extra 10%, when making biodiesel. It will make the same quality biodiesel as pure methanol. It might even make better biodiesel because the biodiesel will work as a cosolvent.

Logan Vilas

100% Right on.

Any methanol you use in the 3/27; 1/9; 25/225; or even 100/900 is fully re-useable in your next batch.

As Logan correctly points out, the co-solvent effect of the glycerides already dissolved in your reused methanol can shorten your next batch time.

Hello producer
I thought reaction time was more of a function of temperature, Amount of chemicals present and mixing vigour.
I do not understand how any co-solvent affect from the odd mono or di glyceride present in the methanol used in the reaction would significantly reduce reaction time.
Surely once everything is mixed, which in my reactors took about 20 seconds to accomplish, you will start to have lots of glycerides present and a few extra from the Warnqvest test would not matter much one way or the other.
Actually, as I think about it, wouldn't these glycerides in the methanol from the warnqvest test have been converted into biodiesel as soon as the NaOH/KOH were added to the methanol to make the methoxide in any case?.
[/b]

quote:

Originally posted by producer:
As Logan correctly points out, the co-solvent effect of the glycerides already dissolved in your reused methanol can shorten your next batch time.

Logan,

I appreciate your interest in getting the best info possible out of this test.

quote:

This test should be done as first designed 25/225. Or for even a better chance of getting it right use this test as 100/900

Have you done any tests which show a different result doing the test at different sizes?

I understand that if you have fallout, it will be easier to measure in bigger batches.

quote:

This is exactly what is wrong with the 3/27 test. It is too small of a proportion. It will probably take 0.10ml of dropout for you to clearly see.

I had been doing the test as 3/27 until I got these tubes. I have attached a pic of 3 tests I did the other night. Tube 1 is my reference sample which tested .2548% total glyceride by GC. Tube 2 is my last batch at 1 hr. Tube 3 is the same batch at 2 hrs. I did this test as 2/9 at 42 f to force a fail so I could compare the amount of fallout.

Tube 1 .6ml fallout
Tube 2 .5ml fallout
Tube 3 .05ml fallout (approx.)

I ran this batch at 19% methanol, single stage. I expected it to take 2 hours or more, since the last batch at 20% had. I was surpirsed when the stuff from 1 hr. passed. The reason I did this test is to see if it continued to covert further by running longer. Clearly, it did.

Andrew

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

Alright Andrew, you know the rules. You can't post pictures of cool gear like that without telling us where we can buy it!

-Jim

Jim,

I have to say, I don't know where to buy them... One of the super friendly people here sent me those as a gift. I will ask him, but I think he got a buch on Ebay. Someone else may know where to get them though.

Andrew

Jim,

They are graduated centrifuge tubes.

You should be able to get them from any major scientific glassware stockist.

Tilly - what is generally understood to be a reaction mechanism (say for example oil + alcohol in presence of catalyst = water + ester) is usually not the true reaction mechanism. Usually a reaction occurs via what is known as a reaction pathway - a series of steps (reactions) that occur, to give the overall result as given above.
Now, there is always one step that is slower than the others, so if you can bypass that step (via say, a different reaction path) then you can speed up a reaction. If the slowest part of this reaction is related to the triglyceride, then reacting with mono or diglycerides may result in a slightly faster reaction. However I would suggest that once they are consumed, the reaction would probably continue as normal (however, there are some other factors that come into play here)

Perhaps what they were referring to, is that since the polarity of the diglyceride and monoglyceride molecules, is between that of the triglycerides and methanol, that they might assist in the initial solvation of the methanol in the oil, which then will have an impact on reaction rate.

I'd like to clarify futher, but my knowledge of reaction engineering is still in its early stages.

Which heet are you using for this test, the yellow bottle or the red iso-heet?

OK, I ordered some 250mL ones with caps. I have them on my site:

http://www.fryerpower.com/store/page2.html

They are at bottom of the page, so scroll down. If the shipping calculator comes up with something screwy let me know and I will refund as needed. I will be able to ship them as soon as they come in.

They are big enough that you should be able to do the 25/225 with no problems. They look like the one on the right in the photo.

$3 each.

centrifuge_tubes.jpg (3 KB, 62 downloads)