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Wow now I am a bit confused........well maybe a bit more than a bit. All the other info I have been reading states that you only mix for 20 mins. (aprox) then let it sit w/ heat on for 12 (+ or - )No pump running. This is the reason I ordered a bucket heater. Your info on the other hand says to pump w/ heat on. Your reference articles seem to suggest 2 hrs. run time w/heat. So........ I am confused. Is it possible that both methods work or ?????????????
Thanks again. Bill
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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Bill,
No, both methods do not work.
Do you recall that you started this thread saying "My history with A/E has been poor at best."
If you are only running the reaction for 20 minutes that is not enough time for the reaction to complete.
The AE reaction occurs in the oil phase. Methanol and oil are not miscible so if you do not keep mixing them together they will quickly separate and the reaction stops.

I find that reaction time depends on a number of things and can not be locked in. My reaction times are usually more than 2 hours. I do an hourly titration and when the titration stops falling I know the reaction is finished.

If I then allow the waste to settle out the titration will fall further because the H2SO4 settles out with the waste. This settling out is not a continuation of the reaction.

quote:
Originally posted by BuilderBill:
Wow now I am a bit confused........well maybe a bit more than a bit. All the other info I have been reading states that you only mix for 20 mins. (aprox) then let it sit w/ heat on for 12 (+ or - )No pump running. This is the reason I ordered a bucket heater. Your info on the other hand says to pump w/ heat on. Your reference articles seem to suggest 2 hrs. run time w/heat. So........ I am confused. Is it possible that both methods work or ?????????????
Thanks again. Bill
 
Registered: January 07, 2012Reply With QuoteReport This Post
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quote:
For all practical purposesTHE REACTION DOES NOT CONTINUE AFTER YOU TURN THE PUMP OFF

That is the biggest load of BS I've read in a long time good on you tilly![IMG]



" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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That is an interesting graph.
    *Is this a graph of some work you performed?
    *Is the graph the results of a controlled test comparing two different Acid Esterifiction methods using identical oil, temperatures, and amounts of chemicals with the only difference being the type of agitation used?
    *Was the 50 titration using NaOH or KOH?
    *What was the total amounts of WVO, Methanol, and Sulphuric acid used in each reaction?
    *What was the temperature of the reactions performed at?
    *Did you run the mixer for the entire 55 hours in the test using continuous mixing.
    *How long did you run the mixer for in the non mixing test?
    *What type of reactor was used?
    *When the periodic titration of the oil was performed where was the sample drawn from?
    *When the periodic titrations were performed was the oil sample first thoroughly washed?

    *It says the reaction ran for 55 hours but the time marks go from 1 to 5. Is the time scale linear?


Any additional information you can think of will be appreciated.
A link to the original website where this test was first posted and described would be really useful.

Thank you

quote:
Originally posted by Biotom:

This message has been edited. Last edited by: BioGoGo,
 
Registered: January 07, 2012Reply With QuoteReport This Post
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this work was produced by buckeyebiodiesel (someone I concider a very good friend) there are several more graphs on the acid esterfication thread, and I'm sure many of your questions will be answered there.


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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It is a shame that you are unable to provide any information about this chart.
If buckeye biodiesel is a good friend of yours maybe you could have him answer my questions.

There is a certain amount of information available from the chart though.
The first thing you see is that the reaction finished when the titration hit 20. This is shown by the fact that the mixing reaction titration stops decreasing when it hits 20. Further mixing had no real affect on the mixing titration.

The next thing you see is that the oil was almost certainly not washed before the periodic titrations were performed. This is indicated by the fact that the unmixing oil continued to slowly decrease in titration after reaching the 20 titration while the mixed titration did not continue to fall.
This was because the sulphuric acid was settling out of the unmixed oil and not an indication of a continuing reaction in the unmixed oil. On the other hand the titration of the mixed reaction did not continue to fall after it hit 20 which means that the sulphuric acid was being continually mixed into oil and was providing some of the titration number.

The problem with not thoroughly washing the oil to remove all sulphuric acid before titrating in this situation is that you are not getting a true indication of how far the esterification of the oil has actually gone which I assume is what this chart is attempting to show.

If you can come up with any more information about this chart I would be interested to hear it.





quote:
Originally posted by Biotom:
this work was produced by buckeyebiodiesel (someone I concider a very good friend) there are several more graphs on the acid esterfication thread, and I'm sure many of your questions will be answered there.
 
Registered: January 07, 2012Reply With QuoteReport This Post



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1) both samples where from the same oil
2) the only differance being one sample was mixed just enought to encorporate all the chemicals and the other was mixed during the reaction time
3) samples for t where taken from the middle of the test beaker/jar but no additional mixing was done prior to removing the test sample
4) even after settling the mixed sample had a higher titration value

I agree that in the sample that was mixed continuously the acid would affect the titration, but not to any great degree since 1ml of acid/ltr of oil increases the value by 2 - 2.4 depending on the purity of the chemicals. As home brewers a simple value of 2 is certanly in the ball park.
If one realy wants to know how well the process worked simply mix up the sample check T deduct the acid value and the results from AE are evident.
When I can routinely do AE on oil Titrating 10 - 16 and have ending T at .75 - 1.5 with minimal amount of mixing, all the literature you can produce will not change that fact. Them that can do and others read and preach about it!


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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Thank you for this information.
Amounts of chemicals and reaction temperature and times would be really helpful.
It would be much more helpful if you would provide a link to where this graph was originally posted.

Just a quick word about the difference in titration that only occurred after the reaction finished at Titration 20. If I use the formula T-3* 0.16 to find the amount of Sulphuric acid to use with WVO titrating 50, it comes out to around 7.5ml sulphuric acid per liter of WVO.
Using your figure of an increase titration of 2 for each ml of sulphuric acid used, the Sulphuric Acid accounts for 15 of the total titrtion number. This is not an insignificant amount and is the reason for the titration difference after the reaction stopped.

I will just point out that it is your claim that the reaction requires minimal mixing and even works better if it is not mixed that disagrees with the mechanics of the chemical reaction involved and controlled testing performed at several universities.

I have spent some time reading through the AE thread in this forum and find many instances of people achieving very successful quick reactions when mixing for the entire time while at the same time people have reported disappointing results using the no mixing method.


quote:
Originally posted by Biotom:
1) both samples where from the same oil
2) the only differance being one sample was mixed just enought to encorporate all the chemicals and the other was mixed during the reaction time
3) samples for t where taken from the middle of the test beaker/jar but no additional mixing was done prior to removing the test sample
4) even after settling the mixed sample had a higher titration value

I agree that in the sample that was mixed continuously the acid would affect the titration, but not to any great degree since 1ml of acid/ltr of oil increases the value by 2 - 2.4 depending on the purity of the chemicals. As home brewers a simple value of 2 is certanly in the ball park.
If one realy wants to know how well the process worked simply mix up the sample check T deduct the acid value and the results from AE are evident.
When I can routinely do AE on oil Titrating 10 - 16 and have ending T at .75 - 1.5 with minimal amount of mixing, all the literature you can produce will not change that fact. Them that can do and others read and preach about it!
 
Registered: January 07, 2012Reply With QuoteReport This Post
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Really!! Eek Big Grin, actually people have disapointing results for various reasons, but mixing is not one of them!!! Wink I don't care what your university lab reults state! If what you say or they state is true then I shouldn't be getting the results I do, it should be impossible. WOW now we are doing the imposible Big Grin Big Grin Big Grin

Edit.. one more thing to think about, when you run the oil though our high shear pumps fatty acids are broken away from the glycerin backbone causing the T to increase. the purpose of ae is to convert the ffa in the oil, not to create more ffa. Therefore minimal mixing should be carried out.


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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I gotta hand it to you biotom, you got me on that one. You really had me convinced that my high shear pump is whacking the fatty acids off the glycerine and raising the T of my oil while doing ae.
When I mentioned this problem to my good friend who got me started making biodiesel he said that he thought this to be very unlikely.

A quick background. About 2 or 3 months ago with the help of my friend I made a small 25 gallon processor. Because my oil usually titrates around 8 I always do an ae stage first. I use the dkenny method because my friend recommended it. It usually takes about 3 or 4 hours for the as stage to finish and then I normally go onto the KOH stage without draining.

After reading your warning about pumps increasing the T of the oil and my friend not agreeing I decided to do a little test to see who was right.
I put 5 gallons of oil titrating 8.5 into my reactor and heated it to 140 deg. I figured that because I am only using 5 gallons of WVO instead of 25 gallons every hour of pumping the 5 gallons around would be equivalent to pumping for 5 hours when actually running the 25 gallon reaction.

After 1 hour of mixing I took out a sample and found the T to still be 8.5.
At the end of the second hour I checked another sample and the T was still 8.5
I continued mixing for 8 and 1/2 hours which would be the equivalent of over 40 hours mixing a 25 gallon batch and the T is still 8.5

So we can all rest easy. Our high shear pumps are not whacking fatty acids off the glycerin.

quote:
Originally posted by Biotom:
Edit.. one more thing to think about, when you run the oil though our high shear pumps fatty acids are broken away from the glycerin backbone causing the T to increase. the purpose of ae is to convert the ffa in the oil, not to create more ffa. Therefore minimal mixing should be carried out.
 
Registered: September 03, 2012Reply With QuoteReport This Post
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i'll bring this back to life if no one else will!
What are we calling a high shear pump?
after not producing for a year i'm gonna try and get back in the game, with out looking at my notes i'm thinking that your quantity of H2SO4 is on the high side. i'm my version of dkenny's method uses around .08 for the H2SO4 multiplier. i can't remember if the pump ran all the time or not i'll have to find my notes.
my hats off to BioTom, a few years ago we worked on modifing the dkenny method and he schooled me in the processes. thanks Tom
Back to the high shear pump, the best i can remember in the commercial process that is what they use and they are able to produce with out caustic. that is why i was asking what you're definition of a pump was. i highly doubt our home-brew bombs have a "high shear" pump on them, which would explain alot.
on another note IT ALWAYS WORKS IN A LAB, but not so much in the real world or our backyard.
Jonathan
 
Location: southern IL | Registered: October 11, 2008Reply With QuoteReport This Post
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