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Qwarla · 26 February 2019, 08:00 PM

Re: Fat fail

tits of 8 are a bit high for my liking. Dig a hole and bury it.

Johnnojack · 28 February 2019, 02:03 PM

Re: Fat fail

Not the answer I need, especially as I used around $50 worth of methanol.

tillyfromparadise · 28 February 2019, 02:54 PM

Re: Fat fail

Hi Johnojack,

I assume you used KOH in the reaction.
I have done virtually no experimentation with high titration Fat and KOH, all my experimenting was on high titration fat and NaOH.
How much methanol did you use per litre of WVO?
How much KOH did you use per litre of WVO?

If it were me, I would mix up the contents of the reactor and then do some one litre test batches using the contents of the reactor.
I would start by adding the missing 3.5g KOH to 10ml or less of methanol and see if that will "push" the 1 litre test batch reaction to completion.
If that did not work, I would do another test litre and increase the KOH to 4.5g.

If you do this let us know what happened

Johnnojack · 28 February 2019, 06:33 PM

Re: Fat fail

Thanks Tilly, I use CaOH not KOH I used 8 grams per litre, should have been 11.5 doh! Haven't made bio for over a year and was a bit rushed at the time and it was stinking hot. The mix went the usual chocolate brown when I added the methoxide then started to thicken up. I thought the temperature had got too low as it was down to 46deg but when I tried to heat up a small batch it didn't seem to melt like normal fat instead bubbled away as if the methanol was boiling off. I don't know why I didnt just get a part conversion, instead it seems to be solid fat which reeks of methanol when you agitate it. I did mix the hell out of it for well over an hour until I realised it was futile.
Will try a test batch in a bottle.

Tony From West Oz · 1 March 2019, 02:09 AM

Re: Fat fail

Johnnojack,
The advice Tilly gave

If it were me, I would mix up the contents of the reactor and then do some one litre test batches using the contents of the reactor.
I would start by adding the missing 3.5g KOH to 10ml or less of methanol and see if that will "push" the 1 litre test batch reaction to completion.
If that did not work, I would do another test litre and increase the KOH to 4.5g.

is spot on. Just change the KOH to CaOH and follow his process until you get a good separation. then scale up the proportions needed and then reprocess the rest of the batch.

Have fun,
Tony
ps, It seems to me that people normally use NaOH or KOH for their biodiesel process caustic. Is there a reason that you are using CaOH?

tillyfromparadise · 1 March 2019, 08:42 PM

Re: Fat fail

Hi Johnojack

Originally posted by Johnnojack View Post

The mix went the usual chocolate brown when I added the methoxide then started to thicken up. I thought the temperature had got too low as it was down to 46deg but when I tried to heat up a small batch it didn't seem to melt like normal fat instead bubbled away as if the methanol was boiling off.
I don't know why I didnt just get a part conversion, instead it seems to be solid fat which reeks of methanol when you agitate it.

I assume you mean NaOH and not CaOH.
What you describe is "classic" not-enough-caustic-in-the-reaction.

Assuming you are using enough chemicals (Which you didn't), when you add the methoxide to the WVO, after a minute or five (depending on the vigor of the mixer and the temperature of the contents of the reactor) the contents of the reactor suddenly becomes much thicker and much more viscous and then after a short time just as suddenly becomes thinner and much less viscous.
The higher the titration of the WVO, the more viscous the oil becomes before finally dropping in viscosity.

HOWEVER, if you do not use enough caustic in the reaction as in your case, the reaction will "Hang up" at the high viscosity stage and the reaction just stops.
All that is required to get the reaction going again is to add the missing caustic (mixed in the minimum amount of methanol required to disolve the NaOH) to the reactor.
You do not want to lose any of the original methanol already in the reactor.

OR possibly there was water in the reaction and you have made a lot of soap. If you have made soap there is no easy fix that I know of.
But I suspect that all you need to do is add the missing Caustic dissolved in a minimum amount of methanol to get the reaction going again.

In experiments I have performed over the years I have "saved" test batches that have sit on the bench in the high viscosity stage for over a day by just adding the missing caustic to the high viscosity litre of glop and mixing vigerously. The reaction then continues as if nothing had happened.
Depending on the viscosity of the contents of the reactor, it may be difficult to mix the methoxide with the contents of the reactor.
I am sure you will figure out something.

Please let us know what happens

Johnnojack · 2 March 2019, 10:05 AM

Re: Fat fail

Oops yes I meant NaOH. The mixture is very thick even in 30 deg heat, it's like thickened cream, the good stuff not cheap brand. I have had it in open drums, had to ladle it out as the reactor is an open one. I have put lids on the drums in an attempt to stop the methanol from evaporating. Not confident of heating it without making the methanol boil off. Maybe in plastic bucket in the solar cooker with lid on tight. This is getting very labour intensive now.

tillyfromparadise · 2 March 2019, 10:56 AM

Re: Fat fail

Hi Johnojack,

The higher the titration, the more viscous the oil becomes.
If you had used the correct amount of NaOH, the oil would still be this viscous at this stage of the reaction. The only difference being that if you had used enough NaOH the oil would have quickly passed through this high viscosity stage and the viscosity would have quickly reduced.

I have "Saved" test batches when the glop was very thick. I just added the extra methoxide to the thick glop and shook vigorously. The thick glop quickly broke and became much thinner and the reaction continued.

If it were me, I would put a litre of the glop into a 2 litre bottle (no heat) add methoxide containing 3.5g NaOH and shake it hard and see what happens.

PS- If you are using reduced methanol that also tends to make the glop more viscous.

Johnnojack · 2 March 2019, 08:42 PM

Re: Fat fail

Ok I mixed 10grams of NaOH with about 50ml of methanol warmed up 2 litres of 'fat' and mixed with paint mixer for 5 minutes. Put lid back on container and left for 4 hrs. Now it is sloppy mix but not exactly a liquid, hmm, will leave overnight and see if it separates.

tillyfromparadise · 3 March 2019, 12:54 AM

Re: Fat fail

Hi Johnojack,

Originally posted by Johnnojack View Post

Ok I mixed 10grams of NaOH with about 50ml of methanol warmed up 2 litres of 'fat' and mixed with paint mixer for 5 minutes.

A word of caution.

"NaOH keeps you honest" when using it in the reaction.
Too much NaOH in the reaction will produce excess soap which can immediately turns the contents of your reactor into glop. I have made many test litres of glop by using too much NaOH in the reaction.
Too little NaOH can result in a "Hung" reaction which also results in a reactor full of glop.
They are different types of glop.

You said you were 3.5g NaOH per litre of WVO short, however you added 5g NaOH per litre of WVO to the 2 litre test batch.
Too much NaOH in the reaction can result in a reactor full of glop.

When you have WVO that requires more than 10g NaOH per litre of WVO in the reaction, you are always very close to making soap that will immediately turn in to a reactor full of glop. Extra care is required in this situation to not use too much NaOH.
This is why so many people (me included) have changed to using KOH. KOH is very forgiving in this situation.

You say your test batch is now a bit liquid.
It is quite possible that by using excess NaOH you have made some soap.

There is a test I have used to see if I have made excess soap.
1. Put about 300ml of the contents of your 2 litre test batch into a Dr Pepper bottle and gently add about 500ml warm water to it.
2. Screw top down tight
3. GENTLY turn the bottle over top to bottom about a half dozen times.
4. If you have soap in the biodiesel it is likely the water will remove some of the soap and you will have a layer of white soapy water on the bottom of the bottle and a layer of biodiesel on top

Is it correct that your WVO titrated 8 NaOH? If not, what was the NaOH titration of the WVO?
How much NaOH did you use in the initial reaction?

If it were me, I would try another test batch using just 3.5g NaOH per litre of glop and see what happens

Some Things That Can Result In Glop When Performing The Reaction Using NaOH
1. Water in the reaction
2. Too much NaOH
3. Not enough NaOH
4. Too little methanol
5. Playing Heavy Metal Music within four meters of the reactor.
6. Many other unknown things

Johnnojack · 3 March 2019, 01:26 PM

Re: Fat fail

Thanks Tilly I didn't know that was the reason people use KOH . When I started making bio about 12 years ago I went to Scotcher fuels to get some methanol etc and they only had NaOH so I got that. After a rocky/gloopy start I have been mostly successful with my infrequent batches. As I said I haven't made any for some time due to time constraints and not needing much diesel anyway. I was a bit apprehensive about the high titration as usually my liquid oil is less than 2 (+ 3.5)
This lot titrated at 8-8.5 so when weighing out the NaOH and the scales clicked over from 8 to 10 I figured it was close enough. Will try the soap test.

Johnnojack · 3 March 2019, 08:54 PM

Re: Fat fail

Tried the soap test, went a bit lumpy so popped the jar in the solar heater and it settled into 4 layers, from bottom, brown water, black byproduct, browny white layer, soap? Top layer of biodiesel. White layer is about 1/3 of the depth of biodiesel layer

Tony From West Oz · 3 March 2019, 10:10 PM

Re: Fat fail

Was this the reprocessed 2 L sample?
If so, repeat with some unprocessed material from that batch as a reference.
Reprocess another 2 L with 3.5 g NaOH in methanol.
Then, tomorrow, do the water test on the 3.5 g Reprocessed batch.

Dr Mark · 3 March 2019, 10:38 PM

Re: Fat fail

Originally posted by Johnnojack View Post

I had an excess of fat which has built up over a couple of years and decided to make bio with it. Much warming in solar cooker, settling and dispensing I had a fairly clean dry batch which was well and truly liquid at 56 degrees or lower. Titration a lot higher than my normal oil at 8.0. Ahhg! Just realised i should have added another 3.5. So it has turned into a creamy mix. What can I do to recover it. I made 90 litres and only have 4 or 5 litres of methanol left.

Hi John,

Your problem is that you were using the wrong method. If you'd used my FRT method you wouldn't have had that problem, and of course you wouldn't have had to bother with a titration.

But as to how to break the emulsion, if anything'll work, it's salting it out. But it probably won't

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