I use a BioPro 150 processor to make my BD. If any other BioPro users can help answer this question, I would be forever thankful.

Situation: The WVO I get titrates a little higher than the limit described in the user's manual (13-15). I dewatered and dried 40 gallons of oil (filtered to 100 microns). I filled the methanol/methoxide tank with methanol until the methanol light came on. I then pressed the reactions button then added 150ml of sulfuric acid to the main tank. After 8 minutes I then added a little more catalyst than the guide requires (1300 grams of NaOH) to the methanol/methoxide tank (600 grams, then 700 grams premixing all the while so as to avoid clumping). I then allowed the process to run and the following morning I saw no separation to indicate a proper reaction. It looked like glycerin, but wasn't as thick. Could this be an indication that I miss measured some where? Just for kicks I added another 250 Grams of NaOH and a little more Methanol. I have the manual stirrer and heater running at this time. Hope to see a better reaction. Any Clues?

You need to run the acid process longer to get the titration down. The preset limits on the machine will not be enough. I have processed WVO titrating at over 20 in my BioPro and got BD that passed 27/3 on the first attempt. Refer to the chart near the top of the AE processing thread for the amount of acid to add. Stir it in with 50 to 60% of the total methanol you use for a few minutes, then leave the heat on and let it set overnight with the heat on, stirrer off. With titration that high you will probably get some water so drain it the next day. Turn on the stirrer to get it thoroughly mixed for a representative sample and titrate again. If it is low enough, 3 or 4 (or better)in my opinion, add the NaOH needed (not the 1200 grams in the manual), add the balance of the methanol and process for an hour or so. You should get separation and probably pass 27/3. If it is still too high, say 8 to 10, you may need to add another .3ml per liter and a couple gallons of methanol and let it set another few hours.

There are a couple extra time consuming steps involved, but you need to let the sulfuric do it's job. Just adding more NaOH is only going to make more soap and lower the conversion ratio, when you do get conversion at all.

This particular batch you are probably going to have to see if you get separation with the Na you added and if it passes 27/3. You can push it to completion, but I would guess you will get a lot of glycerin and maybe 75% conversion.

Thread with Chart

As you can see from the chart, you should have used about 1.75ml per L and you only used 1ml per L.

Norman

Artic b
-I don't have a biopro, but maybe I can shed some lite. you added the methanol, then added 150 ml of sulfuric acid, and, how much time?, later added the methoxide. Seems the acid neutralized the caustic and therefore the reaction if any would be minimal. Tom
-PS once the acid stage is comlete, you have to titrate to find out how much caustic is required for the base process, this will then include the amount required to neutralize the acid.
-for this batch, do a repo and see how far that goes, you my have to repeat it a couple times to pass 3/27.

quote:

Originally posted by Biotom:
Artic b
-I don't have a biopro, but maybe I can shed some lite. you added the methanol, then added 150 ml of sulfuric acid, and, how much time?, later added the methoxide. Seems the acid neutralized the caustic and therefore the reaction if any would be minimal. Tom

Tom--

I assume he followed the auto process with the BioPro which allows for about 6 hours heated stirring for the acid phase to work before the contents of the methoxide tank are pumped over.

Norman

I waited about 10 minutes.I think I need to let the acid work more, allow it more time.

This helps to answer another problem. I've been using too much catalysit (NaOH). I've been having problems with the pump getting clogged and not pumping. I've had to sifon the methoxide from the tank into the main tank in the past and use the manual controls to get it finished. Next time I'll let the acid set ovber night.

StorminNorman:

quote:

add the balance of the methanol and process for an hour or so

When I return after adding the first half of the methanol and acid and letting it sit over night,
do I press the "Reactions" button and then the "Jog" button to skip the first part of the methanol addition phase and then add the appropriate amount of catalyst and remaining methanol (Fill untill the methoxide light comes on)? I think I've been over filling the methoxide tank with too much NaOH and causing other problems to ultimately cause the automated program to "get out of sync".

I would just process in manual mode. After mixing an hour dip a sample out and let it settle out. With KOH it will separate in about 10 minutes, I do not know about NaOH but I do know it is slower to separate. Do a 27/3 test on the BD to see if it is completed or if it needs pushing.

Norman

I'll do that with my next batch. I was able to save my previous batch. It was a bit lower yeild this time, but I've seen worse. Thanks for the AE tip. I was wondering about how the acid converts the FFAs to esters.

I've started a new batch. This time I had the heat going for a few days until I had a full tank (40 gallons) of WVO. I then turned the stirrer on for 6 hours and let it sit overnight with the heat still on (drained the water). I then added the first half of the methanol to the tank and added about 150 ml of sulfuric Acid. I then let it stir for about 20 minutes and then turned the stirrer off, leaving the heat on. Earlier, I took a sample of the WVO and will titrate it today to get a reading.

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

I let the AE stage react for about 24 hours. While that was working I titrated an unreacted sample of WVO. It came to a titration of 7. Add 5 for a base and the required NaOH came to 12. After the AE stage was finished, I titrated again and got a 2. Add 5 for a base comes to 7. (That's a reduction of FFAs by approx. 28.5%). I used about 200g less NaOH to make the reaction (1060g total). I got a 95% yield from this batch (38.1 gallons) I was happy with the results. All I need to do now is a 3/27 test.

ArticBD
-Great results!!! this is just more proof that the ae treament is the way to go with wvo with higher ffa content. Tom

quote:

Originally posted by Biotom:
ArticBD
-Great results!!! this is just more proof that the ae treament is the way to go with wvo with higher ffa content. Tom

Excellant, congrats. I am ready to load for the second batch of my 20 plus oil.

Norman