Hook,

How many milliliters of sulfuric acid did you end up using?

2.5 ml/L

I must be missing something here.

If you start out with 14 and subtract 3, you have 11. Multiply that by .15 and you get 1.65ml/L. OTOH if you start with 14 and subtract 1, you have 13. Multiply that by .15 and you get 1.96ml/L.

Now if you start with 11 & use 2.5ml/L your multiplier would be .227?

Now if you start with 13 & use 2.5ml/L your multiplier would be .192?

Now if you start with 14 & use 2.5ml/L your multipler would be .179.

I need some help here. So far everything looks like smoke and mirrors. Something is not working out mathematically for me here.

DKenny or Biotom please chime in on this conundrum.

I started with a multiplier of .15 for the testing purposes.T-3*.15 The T went down to 4 then back up to 9.
So, I added more methanol( another 10% of the 22% total) and added another 1ml/L of acid for a total of 2.5ml/L of oil.
I think that the relationship between acid/L and methanol/L of oil is a curve. The higher the initial T, the higher the acid multiplier needed and the higher the methanol needed. all in the acid stage only. I also believe that the water created by the side reaction is the cause of this. But, I will leave it to the experts and those handy with graphs to explain what I saw. It may or may not be repeatable. Im just reporting my findings step by step so DK and BT can help makes sense of it.

Hook,

I appreciate your willingness to try this and subject yourself to open scrutiny and I applaud your efforts. My only concern is making sense of it all so that we can replicate it.

If you start with a T of 14 and subtract 3 the result is 11. If your multiplier is .15 the sum is .15*11 = 1.65ml/L. So all I am saying is that if you used 2.5ml/L you are using a different formula from what I have learned here.

I am not trying to be an ***hole, I am only trying to learn something.

yes, it is different, and that is what I was looking for. I used the intitial multiplier of .15 but didnt get results. So, in the interest of testing decided to see what it would take to push it beyond the goal of 3. Frankly, I guessed, and added enough for a total of 2.5 ml/L, or another 200ml for the 245L( i know I said 250L, I was trying to simplify things). The initial amount of acid added was 400 ml, and the additional was 200ml for a total of 600ml to 245L of oil.
Of course it was in 2 stages, and that may play a role.
Scrutinize away, because I am still learning new things with every batch I run.

Thanks Hook. I thought I was being dense.

nope, I just didnt give enough details.

Dave, I have used your method with a multiplier of .18 on oil that T's 9-11 all last year, that's 10 250 gallon batches, my ending T was typically 2-2.5, I always do the one stage base and never had a batch that did not pass 3/27.
My acid stage typically takes 6-7 hours to get to the end point, but I heat to 140F the entire time and my pump does 125gpm so I'm turning my batch over 30 times an hour.
I also centrifuge dry my oil so it is bone dry when I start the acid stage, I believe unless you start with bone dry oil you don't have a snowballs chance in hell of ever getting consistent results.
I always add my 25 or so ounces of acid to 55 gallons of methanol and have never had any type of problem.

hookline
-When I did the acid treatment the temp was constant at 45C (thats what my thermostat is set at, and I process at the same temp)
-So I'm surprised the T only dropped to 7, I'm wondering if it was the heat, this plays a much more important role in the acid stage than I first thought.
-When you added the second bit of acid, did you drain off a few ltrs of junk from the bottom first?, this gets rid of the water that is produced in the first acid stage. also, It's normal for T to initially drop and then after 2 - 3 hr jump, I'm not sure why, but it's more important to know that this does happen. If I read correctly you didn't leave the second acid stage as long as the first one, I wonder what the T would have been.(I know a guy in Winnipeg that has a lot of oil that T's at 15.5 if I can get hold of 150 ltr I will try to duplicate what you did, but at a higher temp, If not, we will never know) I know this takes a lot more time, but you will be surprised how much more bio you get from this batch. for me, acid treatment reduced the byproduct by almost 1/3. thats more bio. Tom

fabricator
-what type of pump do you have? I have to upgrade mine real bad, the NT pump is not sufficient for a 150 ltr batch, even if the methoxid is injected slowly. I can't process using single base stage, and am sure the pump is the issue, and damn I bought 5 thanks for your input TOM
-PS if you can leave the acid stage longer the T should drop to 1.5 or there abouts
- it seems most people add the acid to the methanol, but I'm a bit gun shy at this point. The problem was , not enough methanol, and no head space so you know what happened

I hear ya Tom, I didnt let the 2nd stage run as long, I was happy with where it was at. I didnt drain anything except for samples that were mixed for titration. I am going to try to replicate the scenario next week, keeping the heat at 135-140F (heater on) I normally turn the heater off after reaching the desired temp. Its a modified appleseed, so it is well insulated.
A far as time goes, it doesnt bother me. Im flush with fuel right now, and my storage capacity will be maxed once this batch is washed and dried. Hence me processing next week instead of this week.

hooknline
-I'm interested to know how much extra bio you get from this batch Tom

It's a Scot LFE251A I believe, 2.5 hp 125 GPM 1.5" inlet 1.5" outlet, I did a real world test ant it will move 125 gallons of cold oil in one minute, murphy has some excellent pumps on his site that are more reasonable for smaller volumes, the blue pumps will move around 6-8 GPM on a good day.

me too, as I had to add an extra 4g/L to get it to pass 3/27???????? letting it settle out now.
Im thinking I rushed it and didnt let it go to full reaction on the 2nd acid stage. Being that you see the titration jump towards the end as well, I think the titration would have been a 5 or 6. too much acid maybe.Patience is not one of my better traits.

Hooknline,
good work..so it seems 0.17 or 0.18 might be better than 0.15..too low?..good job on figuring out how to fix the slight oops.. does this depend on the initial titration or the total amount of methanol? if you have more of this oil, try the 0.15 again but use 65-70% methanol to start.
I have long suspected than the amount of methanol need is also titration dependent. I might need to back to ISU document and see if I can figure something out.

Eurocab, yes we, several of us are working together to fine tune the process I put forth a while ago. I need everyone's help, because at the moment I don't have 'bad' oil.

Fabricator, do you have more, can you get more of this oil? I would interesting to see the results if you tried using a 0.15 instead of 0.18?

-dkenny

I have enough bad oil left to try it. Its going to be a few days to a week. I have the wash tank full and the processor full right now. Ill try to be more patient on this next one. In the interest of science of course.

hooknline
ya patients isn't my strong suit either. I found that the extra acid is very easily neutralzed by the KOH T solution. I did acid stripping with the byproduct , and although the starting ph was 8. it still took .75gr to reach 8.5.
-on the other hand, the sample I took prior to acid stipping had a starting ph of 1.5 and T'ed at 1.25 so you can see, the differance from ph 1.5 acicdic to 8.0 caustic was .50gr KOh Tom

quote:

Originally posted by dkenny:
Hooknline,
good work..so it seems 0.17 or 0.18 might be better than 0.15..too low?..good job on figuring out how to fix the slight oops.. does this depend on the initial titration or the total amount of methanol? if you have more of this oil, try the 0.15 again but use 65-70% methanol to start.
I have long suspected than the amount of methanol need is also titration dependent. I might need to back to ISU document and see if I can figure something out.

Eurocab, yes we, several of us are working together to fine tune the process I put forth a while ago. I need everyone's help, because at the moment I don't have 'bad' oil.

Fabricator, do you have more, can you get more of this oil? I would interesting to see the results if you tried using a 0.15 instead of 0.18?

-dkenny

I have 3000 gallons right now, I'll work my way down from .18 to .15 over the course of the next few batches.

I got the most nasty WVO in the earth (currently in china)

Titrate at 65 KOH... I used the dkenny formula and got down to 8-10 KOH using 2 or 3 acid stages

I don't wanna go further, i think 8koh should be good enough. Got about 90% yield, which is not bad.

I am planning to make a 1 ton machine..but the problem will be the pump, the pump will be huge...and the eletric bill will be very expansive for acid stage!....it's like few K Watt for 24hour mixing.....


Dkenny, is it possible to cut down the mixing time for the acid stage?...lots of people saying we should make it for 24hours, and settle for some hours and drain...i am hoping to cut down the mixing hours.