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First time AE, a little help please....
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HI all,
Got 225 gallons of mystery oil yesterday.

Titrates at 20 KOH. (how much is that NaOH anyway?)
I want to do AE to lower this, preferrably just the single acid stage, that should do right?

I have read so many threads on this my head is spinning... what is the most current formula used to determine the amount of acid?

My plans is to:
- Dry oil
- peform acid stage with half of the methanol (11%) until T stops dropping.
- Perform base stage with remaining 11% methanol and ordinary amount of KOH based on the base number plus the ending titration number.

Is that right? Is a single Acid stage enough? What is the latest formula to determine the amount of acid?

Thanks so much,
Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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at 20KOH you should consider drain between the acid and base stages..
this will help lower the ending titration and remove water..

water in the base stage make soap..as such it kills the yield..not good.

draw back you need to add an equalivant amount of methanol that you drained..as in you drain 3 gallons you'll need to add this 3 gallon of new methanol to the 11%..

yes a single acid stage should be enough.

HTP test is the start of DRY!!! think checking the vapor coming out of you drying setup..none is dry.

try 0.15 times titration.. or 0.1 times titration..depends on how dry and clean you oil really is.

keep us informed.


time for dinner or I might write more..

-dkenny


'84 bluebird school bus, DD8.2L turbo( 4/2011, the bus tranny has died..Frown 8.23.11 bus driven to scrap yard Frown )
2006 Jeep Liberty CRD Smile - the wife's
99 dodge 2500 5.9l 24v..-mine Smile
everything run B100 when its warm enough Smile
 
Location: RTP, North Carolina | Registered: December 15, 2004Reply With QuoteReport This Post
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Thanks very much!

Ok, so single acid stage is enough, sweet!

I do 80 gal (300 liter) batches and let's say I go with the middle of the road of what you suggested in terms of acid quantity, the math would look like this, I hope:

0.125 x 20 x 300 = 750ml of acid.

Then I assume I need to adjust for purity, I am getting 93% H2SO4 so 750 / 0.93 = 806.45 ml of my acid, yes?

If I add 11% (33 liters) Methanol for the acid stage, how much should I drain? and how long should it settle before I do that? I am still curious if I will have to take it off the top or the bottom?

Sounds like I can still do all this without letting the mixture cool off too much, that would be nice since heating is always very energy intensive.

So do I have it totally right? I am ready to go and want to do this tomorrow starting in the early mornin'.

Lastly, I have made a great connection for Phosphoric and Sulfuric Acid (93%) in the Central Valley of California just south of Fresno. If anyone is interested, just PM me. I am also working on a local connection for KOH and NAOH at potentially Fantastic prices through a local soap manufacturer.

Thanks again, I can't wait until tomorrow...

Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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don't adjust for purity...
why? its easier to add more acid later than to remove acid..

if you drain it'll be 1/2 of 33 liters.. or about 16 liters...give or take

if all goes as it should the draining should come off the bottom..too much methanol..too low a starting titration..not enough acid( unusual ) the mix will float..yours should sink without question.

you shouldn't use phosphoric acid for AE, but for treating the glycerin after the base stage..
that's a different game between KOH and phosphoric acid lead to.. it late but it make a good fertiliser..if I recall great for grapes and wines...


ah keeping things hot..the other draw back to AE..insulate..everything..R19 or better..
if you can start HOT!! 165F...but not over say 185F..unless you can pressurise safely..Most people cannot run pressure!!around 190-195 it very hard to use a pump to inject the methanol/acid mix. I've tried it took me over an hour to ad 6 gallons. the pump kept cavitating..normal is about 10 minutes.
there is not need to add the methanol/acid mix slowly.

-dkenny


'84 bluebird school bus, DD8.2L turbo( 4/2011, the bus tranny has died..Frown 8.23.11 bus driven to scrap yard Frown )
2006 Jeep Liberty CRD Smile - the wife's
99 dodge 2500 5.9l 24v..-mine Smile
everything run B100 when its warm enough Smile
 
Location: RTP, North Carolina | Registered: December 15, 2004Reply With QuoteReport This Post
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Thanks dkenny!

Here we go.....
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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Just an update, right now, after 2.5 hours of mixing at 125 degrees F., titration is down from 20 to 10... Nice!!!

Does this indicate that I'll be done in a couple of more hours? Or do you think we're talking overnight?

Thanks,
Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post



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Update, now 5 hours in and it is titrating at 7.

Question: How high of an initial KOH titration can be tolerated when using acid, WITHOUT having to drain in between acid and base? I am asking since that drain suddenly adds 9 more gallons of Methanol to the process which ends up adding 50 cents per gallon to my cost.... quite a lot!

Also, can I drain less than the recommended 50% ? Say 25% ?

Thanks, if I can get some better oil then I can mix the two and hopefully get a titration that is low enough to not have to drain. Thoughts???

Thanks,
Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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-At T7 you are close to the lowest t expected, 2.5 ml acid/ltre of oil X 2 = T5 thats an awsome reaction in that lenght of time at that temp!
-drain as much junk off the bottom as you can , you will probably hit oil long before you get 50% of the methanol volume drained. I drain the really black stuff then stop, each batch is slightly different. Don't go to Base stage without getting rid of the water and as much acid as you can, AE process creates water and carried to base stage this enhances soap production and reduces yield.
-I blend oil all the time it is a good way to lower T. others would take advantage of the good oil and go straight to base process and treat the bad oil as you have done. Tom


" 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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Thanks Biotom!

Titrated again, now after 8 hours T is 6.5

So in effect I will be base reacting with oil that presumably ends up KOH titrated around 6 - 6.5 and that is ok? How high of a T can one tolerate going into base reaction? Does it make sense to drain and reprocess with acid again to further lower T?
I hope it doesn't because this acid thing is taking forever already, though I am very happy that it is in fact possible to make good fuel with crappy oil :-)

Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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Well, final T was 6.5, then I settled for several hours and drained almost 2 gallons of brown water/acid, not too bad assuming everything went well.
Then I base reacted as normal using KOH based on the 6.5 T.
Now it is settling, and has been for a few hours, I am not able to distinguish a separation line through my poly settling tank, perhaps the acid always makes the final diesel darker? I did mix the acid with the Methanol before adding to the oil by the way.
Anyway, tomorrow I will certainly find out if I have separation when I try to drain...
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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yes the biodiesel will be a darker color but you should have no trouble seeing the byproduct layer after that length of time. did you pass 3/27 before shuting down the process? Tom


" 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 thought I did pass 3/27, but must have been too sloppy because after having a bit of an emulsion problem washing I checked again and had maybe a tenth of an ml settle out. I will probably just blend that batch since it is not that much but need to make an adjustment on my next batch. I suppose I will add more KOH but not sure how much more... any ideas how to determine that?
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post



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-Did you dry the washed fuel well before doing the second 3/27 test. this test will not work reliably on wet biodiesel. having said that, it did sound to me from your previous post that this batch was under reacted. emulsion can be caused by underreacted fuel, but even more so by allowing byproduct into the wash cycle, it doesn't take much byproduct to cause big emulsion problems.
-I have had similar results with 3/27 after wash and dry even though it was a clear pass prior to washing. I assume and I could be wrong, that after wash and dry,there is a full 3ml of biodiesel in the test, and after a few miuntes of settling out of the processor there is both methanol and a small amount of byproduct in the test. Tom


" 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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Yes, I suppose that could be it.

When you do 3/27 'in process' to determine if reaction is complete do you quickly dry the oil first? Will water really make otherwise fully reacted diesel precipitate out drops of oil and make it look under-reacted? Or does it cause a different type of 'fail'?

Thanks Tom!

Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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Dan
quote:
When you do 3/27 'in process' to determine if reaction is complete do you quickly dry the oil first?

there is no need to dry the oil coming out of the reaction process to carry out 3/27, just let the byproduct seperate for 20 minutes or so. I leave the processor on while I await the results of the test. If you do the 3/27 with wet biodiesel, as you would have during the wash process, you will get a false fail! Tom


" 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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Thanks Tom, that makes sense.

As mentioned I was going to just blend this batch with the next one. But the next one also ended up a bit under-reacted. I'm trying to learn more about how to adjust the meth and koh appropriately to improve the process without overdoing it, how do you know which one you are low on?
Anyway, I started a new thread about the latest batch in the Biodiesel Quality area if you want to take a look since I think I'll need to reprocess. I appreciate your help.

Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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jajada,

sorry if this question is late..but..next time..
after you drained the mixing from the bottom did you remix..I might have missed that part..you should mix after drain then titrate..you might have found the ending T lower than 6.5..

how high can KOH process..I not claim the highest by any means but T13 is possible, but yield will be terrible!!

-dkenny


'84 bluebird school bus, DD8.2L turbo( 4/2011, the bus tranny has died..Frown 8.23.11 bus driven to scrap yard Frown )
2006 Jeep Liberty CRD Smile - the wife's
99 dodge 2500 5.9l 24v..-mine Smile
everything run B100 when its warm enough Smile
 
Location: RTP, North Carolina | Registered: December 15, 2004Reply With QuoteReport This Post
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dkenny,
Yes, I did mix and titrate, thanks for checking.

I am very impressed with the AE process, the second batch I made with the same oil I added a bit more sulf. acid and ended up with titration dropping all the way from 20 to 4.3.
If anyone is interested I used 1290 grams of 93% sulf. acid. in 300 liters of oil (~80 gals).

For next batch with this oil I will repeat the acid step and then increase the amount of KOH in the base stage while keeping methanol at my usual 22%.

Any thoughts on how much to increase the KOH?
I had 3 to 4 percent unreacted oil in my 3/27 test on the first batch so perhaps increase it by that much for a start?
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post



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Dan
with KOH I found that a two base stage worked much better after AE than single base. Tom


" 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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Thanks, maybe I'll try it, but all these cycles are killing my time and energy spent on this :-( My HF pumps don't have thermal shut-off which keeps me pretty engaged anytime a pump is running. I also don't yet have a flow switch on my inline 1000w heaters. Once I left one on for just a few seconds after shutting off the pump and it managed to melt the insulation wrap very rapidly. I would say it's a guaranteed fire if left unattended with a stuck pump. But I digress.... I take it you use 80/20 two stage, yes? Total of 22% meth and 7.7g 90%KOH plus T ? This was not enough for me last time, maybe two stage will get it done with same amount of chemicals.....thoughts?

Thanks,
Dan
 
Location: Central California | Registered: April 24, 2010Reply With QuoteReport This Post
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