Hi All, I did 3 1/liter test batch and they're good & pass the test but now I tried a 152 liter batch but the titraion won't drop below 5 what should I do I already add 260ml of acid. did I loose this batch or I could save it, the batch is dewater.I can't figure out what I'm doing wrong

sometime it just works that way. just proceed with the base stage using KOH.


-dkenny

thanks dkenny, I never used that product is that so thing I can pick up at the hardware? also what would be the ratio I've always use NOah 3.5 plus the titration is it the same process?

not sure if you can get KOH at the hardware. in NC no. at your location maybe. you might look at industrial chemical suppliers

if you cannot get any KOH, start with the 3.5 grams NaOH as normal. but test with the 27/3 test after its mixed for 2 hrs. if it passes then wash and dry. if not, let settle then drain some/most of the glycerin then reprocess. repeat until it passes.


-dkenny

ps just in case you don't know, you can use the 27/3 test to test unwashed fuel.

I'm going to call my chem supplier tomorrow I don't see any problems in getting it, I was just wondering if there was something I could use right now for a test batch, I'm paying $20 for sack of NaOH at the moment and 220 for drum of meth the acid I pickup at the corner store $5/Liter.

I picked up a bag of KOH last night it's 90% is this % normal the other one they had was 45%. I titrated the batch I had started the acid part and it was 7.5 now. I pulled 500ml from my large batch to test with I added the 7.5+3.5/2 since it's only half a liter mixed in half of the prep mix and add the balance after I reach the temp of 130 mixed by hand for about five mins since it was late I let it sit overnite I checked this morning and no reaction I remembered today I was to add 1.4 to my base which I didn't, today I'll add the deference and reprocess.

Charger,

Yes. My KOH flake is 90% purity.

With KOH purity at that level, a titration of 7 isn't all that bad. You would use this formula

Let's say that you are processing 100 liters of WVO.

700/.9 = 778 grams of lye (adjusted for purity).

Titration of 7. (assuming you put 1 gram of Lye in with 1 Liter of oil for your test solution).

Put in another 700 Grams of lye (not adjusted for purity because your solution is graded for your lye)

1,478 grams total of Lye in 22 Liters of Methanol.


Just my $0.02.

PwrStrk6spd

Hi PwrStrk,
thanks you for your input every $.02 help, I'm still using NaOh for titration, I admit I still need to learn a few thing when working with KOH I need to learn how to (adjust for purity) & neutralize acid. I arrived to almost the same number as your example a little different if this is the correct way I don't know, but it did work I'm going to measure the yield of the test batch tonight I'll keep you posted of the progress.
Here's the way I came to my number
100liters wvo
7 titration
3.5 base
1.4 for adjustment
7+3.5x1.4x100=1470grams of lye the meth was the same as yours. Is this enough to cancel out the 210mls of acid used in the acid step 7+3.5x.2x100=210?

Thanks
chargerpr

chargerpr,
working KOH is the same as working with NaOH. you just make the titration solution from 1g KOH and use 8g for the base instead of 5g for NaOH. your 3.5g for the base when using NaOH is out of date.

there is no neutralization needed.
the titration after the acid stage tell you how much it use. it cannot tell if the acid value is from H2SO4 or FFA's

-dkenny

Hi dkenny I'll make a new titration solution batch today and do another mini batch using your recommended base. Can I still use meth to to perform the titration? Is there a limit on how much of KOH can a person use before the batch goes bad. I'm starting my new solution I just remembered when I start my next 40gal batch for the 1st stage is my base 8 also?

thanks
chargerpr

if you're doing acid/base, then the first stage is acid...no base..

if you're talking the first base stage then yes use 8g. I usually process anything with a titration over 7 with acid/base. 7 and under base only.

so KOH= 8g(base) + titration(using KOH solution).

methanol depends on what stage you're doing.
12% of oil volume first acid stage
8% of oil for first base stage.

20% for single stage base

but all should pass 27/3 before they're done and before washing.

methanol is fine for titration but most use isopropyl alcohol (90%).

-dkenny

ok thanks, when you do the single stage method using KOH how long to you process for? When I used NaOH I processed for 4hrs and settle for 8hrs min. for the acid/base method the base stage how long should it process for 2hrs? I'm using a 55gal reactor but I only process 40gal batches.

usually between 1-3 hrs for any base stage( base only or base part of acid/base).
after 1 hr I'll draw a sample to run a 27/3 test after it settles(about 10 minutes). if it passes its done. if its not done I'll let it run another hour and recheck. if after 3 hrs its not done. I let it settle, then drain most of the glycerin and reprocess. this is repeated as many times as necessary to pass 27/3.

-dkenny

Hi All I was able to check the batch today, I performed the 27/3 and didn't pass I drain about 10gal of by-product and mixed for a little bit and pulled a mini batch so I can get the final number. When you reprocess you use the same amount of meth you started with for base? I did a new solution of KOH used the same method I did for NaOH but is there a way I could check it's correct? Can someone assist me with a clear set of instructions for the 1g solution one I'm using came from another site that is out dated. incase this matters I have a simple scale theat reads only in even numbers it was the only one I could find local.

Thanks
chargerpr

did you run the first base stage before running the 27/3 test? you should have

for reprocessing I use about 1.5 gallon of methanol and 600g of koh. this is somewhere around 50ml/Liter for methanol and 1-1.5gms for KOH.

the solution is made the same way...1gm in 1Liter of distilled water. read the CBT for the more accurate method of making the solutions. it involves using 10gm per Liter the diluting this solution to 0.1%

the titration instruction are the same..

the making changes in that you use 8gms for the base instead of 5. then add the titration amount


-dkenny

Hi All thanks for the info on CBT today I'll be reprocessing the batch I just didn't have time during the week. I have 55 gal of BD that I had processed with NaOH at the high limit and don't dare but anymore it isn't gel but has a wax file on top this was before I switch to KOH. Is it possible for me to reprocress it with KOH?

Hi dkenny I reprocessed a mini batch after I drained 10gal as recommended then remixed the remaining pulled a mini batch after settling, it was about 50/50 it took me 3 tries for it to pass the 27/3 but I noticed each time I reprocess I had less & less settlment and when I got to pass I had no settlment but the BD was a little darker but it's still see thru just the color is a shade darker is this ok and it passed the 27/3? The mini passed the 27/3 on the third try I also added 5gal of the 10gal I had drained earlier since it had resulted in the settlment was being reprocess. I pulled another mini from the drum I had from the last batch that was an unfinished run I reprocessed it but looks like by the time I finish it it will yield about 50% and about 3800grams of KOH is amount ok?

thanks
chargerpr

chargerpr,
the color of the BD doesn't matter..I find that acid/base processed BD tends to be darker than just base processed. I think the acid burn the oil.

you added 5 of the 10 gallons you drained out????
NO...you should add 10 gallons of new methanol to the amount you needed for the base stage. you should have needed 10% of the original oil volume for the methanol volume in the base stage. But since you drained 10 gallons out...most of this is methanol..But this methanol is very acidic..and contains water!

I take the stuff I drained out and save in a container for methanol recovery. I don't use it for anything else.


50% yield is low...but if you used too much acid and proceed with the base stage. yep this might be normal.

-dkenny

dkenny,
I think there's a mis-understanding I'm running 2 tests, 1st acid/base with 40gal the reason added the 5gallons back was because of the results I seen when I did the mini but I also added new meth about 2gal, I was under the impression the first 5gal I drained had most of the water and by-product and the second 5gal was could have been by-product and incomplete reacted oil and that was the one I added back when I completed the mini it had very little to no by-product and pass the 27/3 this way. 2nd The other one I'm working with is a left over incompelet reacted drum that was processed using the base method with NaOH I haven't processed that drum yet the 50% yeild was from the results from the mini using KOH I'm using 50/L of meth for all reprocess portion.
I'm sorry for the disconnect.

chargerpr

Hi Everyone I finally got around to finish my first acid batch that I put on the back burner it was a strange batch first it wouldn't seperate but once it did after I removed the meth I just started to drain the by-product but I notice even though it was dark golden and see thru I thought just for kicks I wanted to see what would the by-product look like in the 27/3 test I performed it expecting to see settlement to my surprize it passed the test is this normal? It's not thick like the other stuff I drain from my other batch that it was black and strong smell. Can BD have 2 density with in the same batch?