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Eeeh Gads it happened again.....only Worse
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O.K. this is what I did -----and what happened

Started with 35 gals. of dirty, high titrating (15) oil. I filtered of course and then dried it (or so I thought) by heating it and air drying in similar fashion to the way I dry finished fuel.I air dried for 4 hrs. I then proceeded with my AE process where I added 3ml/ltr and 7.5 gallons of methanol. I reacted it and let it settle overnight.
This is where it gets bad. In the morning I had about 2gals of dark biodiesel on top and about 40 gals of a tan colored crud below.
Since I was going out of town for 10 days I figured I would deal with it upon my return. (I also figured the bio gods would fix it for me while I was gone) The gods did not smile upon me and now I have 22gals. dark biodiesel on top and 15 gals of tan colored crud on bottom. I believe that my drying methods did not work (probably an understatement) Is there a way to save the 22 gallons of bio on top without adding 15 gallons of methanol. If I added that much methanol my price per gallon would be higher than pump prices.
I thought I had this AE thing down but now it seems I need to get my drying skills refined.
And finally.........HELP
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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Originally posted by BuilderBill:
I then proceeded with my AE process where I added 3ml/ltr and 7.5 gallons of methanol. I reacted it and let it settle overnight...
The gods did not smile upon me and now I have 22gals. dark biodiesel on top and 15 gals of tan colored crud on bottom...HELP
If you have only performed the acid stage it is very unlikely that you have 22 gal of dark biodiesel on top.
 
Location: France | Registered: October 18, 2010Reply With QuoteReport This Post
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Sounds like a pretty dramatic failure. How old is your methanol? Almost sounds like it has been contaminated with water rather than the oil. That or the oil was so wet you should have been able to see settled contamination. Very humid where you are?
 
Registered: February 25, 2010Reply With QuoteReport This Post
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I live in Las Vegas where it is not very humid. 15% in Aug. is bout as bad as it gets. The methanol is not more than 1 or 2 months old, totally sealed drum except for the hand pump. The oil was pretty crappy but titrated at 15 and didn't have visible water. It had settled for days in a separate tank and the bottom inch was drained off before I transferred it to my reactor tank. Where do I go from here? The previous batch with this same oil I did the glycerin pre-treat but was advised against using this method with AE.
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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builder it sounds like you have used too much methanol it makes the byproduct layer float 10% is about max for AE. You did not say what your second titration value is biotom or dkenny should chime in with more precise advice
 
Location: south australia | Registered: November 17, 2008Reply With QuoteReport This Post
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Your right, the gods are not pleased! Big Grin, but you can win. Sounds like the top layer is oil and maybe some biodiesel, if the AE process worked even a little bit. Resting the batch for 10 days won’t cause any problems but the process won’t move forward without heat.
Drain from the bottom, very slowly, about a ¼ cup in the bottom of a bucket, then swirl the drainage and check closely for water. If the oil was very wet water streaks will be evident. Now drain a further two or three ltrs. Then mix the whole batch check T if AE process has failed then add 1ml of acid/ltr of oil mix well (10 minutes) then add methanol equal to the amount of drainage then mix again for another 10 minutes (heated of coarse) and let stand hot over night.
I suspect that the caustic leftover contents in your processor have had angerd the gods Mad. Hope this helps
I know many here mix the acid and methanol together first but I have much better results if I add the chemicals seperatly, methanol first then mix followed be acid and a second 10 minute mix. I'm not sure if this will help your problem but I would give it a try.
EDIT If you check the ph of an AE sample it should be about PH 1, AE will work well at ph up to 1.5, with higher starting PH the effectiveness of the reaction is greatly deminished. If you take an ae sample mixed as you would for T, it only takes .25ml of T solution to bring the PH of the sample to 7. I hope from this you can see the disasterous effect that a small amount of caustic in the processor can have. Tom

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


" 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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Sorry for the delay in responding. I did as you suggested and my initial titration was 13. Added acid and methanol as suggested. The following day (today) I did another titration test and found no change. 13-14 before adding additional acid and 13-14 after adding as prescribed.
Not sure where to go from here but was thinking along the lines of letting this witches brew settle out, draining off the "tan" looking liquid that settles to the bottom and just working with the dark colored liquid that I think is oil. This would mean draining approximately half the volume. I think that I may be able to save this stuff, that is, the top layer.
As always I am more than willing to accept guidance. I need to do something with this batch as I have some better oil to react if I can empty my tank. Thanks Bill
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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what temperature are you keeping the this natch at? sulfuric acid will mop up any water that is in the oil and pull it to the bottom. How much acid is in the batch now, ml/ltr,


" 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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The total acid that I have added is 4ml per ltr. I mixed it at night at 140 degrees and the temperature the next morning was approx 105. I live in Vegas and its still hot here.
Can I wait til this settles out and then drain off the "tan" and then add new oil to the processor and start a new batch? Or can I separate and try to do second stage with the "good" oil that is left after separation? Bill
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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OK 4ml of acid/ltr of oil will add about 8 to the titration (2T for each ml of acid/ltr)if no fatty acids have been esterfied then T should be much higher. drain about 3 ltrs from the bottom, mix well and redo the titration. THEN go to base process, yield will be low but that will clear the tank for the next batch. the resulting biodiesel will be darker than you are used to but good just the same.


" 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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Originally posted by Biotom:
OK 4ml of acid/ltr of oil will add about 8 to the titration (2T for each ml of acid/ltr)if no fatty acids have been esterfied then T should be much higher.
But what about the acid that was neutralized by the leftover caustic in the reactor? That will not show up in the titration will it?
 
Location: France | Registered: October 18, 2010Reply With QuoteReport This Post
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Hello when I go to the base part I am assuming i will used the latest T number, even if its a high number? Will I then add the remaining half of methanol that I started this project with?(that would be 3.5 gals) Let me be more clear. I started with 35 gallons oil and added 3.5 gallons of methanol with my original acid. Then the second time I added 2.5 gallons of methanol with the later 1 ml. acid.
Now after I titrate and get a value, how much more methanol will I add?

Please Santa bring me a centrifuge.
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post



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Another think you need to keep in mind is that there is now more liquid in the reactor. By my calculations you have the original 35 gallons of WVO and another 6 gallons of methanol mixed in it for a total of 41 gallons.
When you did your most recent titration you figured out how much Caustic is needed to neutralize the acid in every litre of liquid in the reactor, not just the WVO you started with.
So when you figure out how much caustic to add you will need to figure the titration amount on the 41 gallons now in the reactor, but the Base amount will only be calculated on the original 35 gallons of oil.
 
Location: The Big Easy | Registered: October 12, 2010Reply With QuoteReport This Post
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mix your methoxide with 100ml of new methanol per ltr of OIL roughly calculated you have 133 ltr of oil * 100 = 13.3 ltrs of methanol.


" 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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So when you figure out how much caustic to add you will need to figure the titration amount on the 41 gallons now in the reactor, but the Base amount will only be calculated on the original 35 gallons of oil.

this is very important, but more so if you use NaOH


" 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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Originally posted by Biotom:
this is very important, but more so if you use NaOH
Why would it be more so if you use NaOH?
 
Location: The Big Easy | Registered: October 12, 2010Reply With QuoteReport This Post
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too much NaOH,+ the extra water from acid neutralisation could result in GLOP, KOH is more forgiving but using too much can cause more soap.


" 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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Originally posted by Biotom:
too much NaOH,+ the extra water from acid neutralisation could result in GLOP, KOH is more forgiving but using too much can cause more soap.
OK, I understand. What you meant was that if you are using NaOH it is always important not to use way too much.
 
Location: The Big Easy | Registered: October 12, 2010Reply With QuoteReport This Post



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Mr Dixieland You may have overlooked the fact that I drained 2.5 gallons twice. Once before I added the second round of acid (1 ml.) and the second time before my final titration, which will be tomorrow. If I had drained nothing I would be at 41 but I am still at 35 due to draining.
I guess more importantly does this change any of my calculations?

If you guys can fix this batch you can do anything.....including driving a vehicle on used vegetable oil. Wait a minute, you do drive............................ :}
 
Location: yes | Registered: July 16, 2011Reply With QuoteReport This Post
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Originally posted by BuilderBill:hich will be tomorrow. If I had drained nothing I would be at 41 but I am still at 35 due to draining.
I guess more importantly does this change any of my calculations?
Calculate the titration amount of caustic on the total amount of liquid remaining in the reactor when you commence the base stage. Make sure the remaining liquid is well stirred before performing the titration
When it comes to the Base amount of caustic to use, there is an uncertainty as to how much oil is in the reactor. If it were me I would assume there is still 35 gallons of oil in the reactor and calculate the base amount accordingly.

Out of curiosity, what are you using NaOH or KOH.
 
Location: The Big Easy | Registered: October 12, 2010Reply With QuoteReport This Post
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