Fat fail

[tillyfromparadise Senior Member Find all posts View Profile Close tillyfromparadise]

Re: Fat fail

Hi Johnnojack,

This sure brings back found memories. These are the type of problems that we often talked about 15 years ago when just about everyone used NaOH.
Now that just about everyone uses KOH instead of NaOH, there is virtually no "glop" produced. You either have separation or you don't.
That is because KOH makes liquid soap, not solid soap.
Even the latest nonsensical "foolproof" procedure that uses 20g KOH per litre of WVO! does not produce glop, it just produces lots of liquid soap that ends up in the glycerine layer.

How much of of the sample that you washed do you think is biodiesel?

Two things I would do
1. I would wash a sample of the glop from the reactor the way you washed the last sample and see what it looked like
2. I would do another reprocess cutting the NaOH back to around 3.5g per litre of WVO

[smithy Senior Member Find all posts View Profile Close smithy]

Re: Fat fail

Hi Johnnojack, one problem with a gloopy batch is that continuous fiddling around with it is very confusing if nothing works, leaving you with more problems. As Tilly says doing trails on small samples is best.

I have never personally had a batch like this but have recovered plenty for other people. I always add glycerol derived from KOH with heat and mixing and the batch always splits. Anyone near you with some liquid KOH glycerol?

After the split you can do a warnqvist test on the oil/bio layer to see roughly the conversion you have achieved.

A few months ago someone brought me 100 litres of jelly (too much added catalyst) after heating to 60degs C and mixing in 60 litres of glycerol I managed to recover 70 litres of biodiesel.

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Fat fail

Tony yes this was the reprocessed sample. It finally settled to about 70% bio 20% glyc and 10% soap. So it looks like it should convert with a bit less catylist. Although with the high titration level I'd expect a bit of soap formation anyway. My problem now is the batch is so solid in consistency that heating it without the original methanol evaporating is a problem. I don't have a sealed converter with an electric element. I normally just pop a few open 20 l drums of oil in the solar cooker on a sunny day and by mid afternoon it is plenty hot enough, if I don't get to it it stays there and will be hot the same time the next day. Simple and safe and has worked well for over a decade, till now.

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fat fail

Johnnojack,

Now is the time to decide whether it is worth your while continuing with the re-processing of this batch. If you lose the methanol then you need to add it back to the heated failed batch. How much do you lose? How much do you need to add into the re-processing?

Do you continue to re-process, or do you write off this batch as a bad experience?

[tillyfromparadise Senior Member Find all posts View Profile Close tillyfromparadise]

Re: Fat fail

Hi Johnojack,

I would not be in a rush to write it off just yet.
You have a reactor full of glop, If you keep it covered I doubt that the methanol will evaporate off too soon.
In past testing I have been able to recover test litres that were quite solid by simply adding the missing methoxide and shaking vigorously.
It surprised me how quickly and easily the glop broke and the reaction resumed.

I would be inclined to do another test batch where I reduced the the amount of NaOH and possibly increased the the methanol slightly.

If that does not work you might even add a small amount of petro-diesel to the reprocess and see if that will make things liquid enough to get the reaction going.

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Fat fail

Tilly the trouble is it isn't 'glop' like in consistency, it is about the consistency of margarine. So mixing anything with it is next to impossible without heating it up.

[tillyfromparadise Senior Member Find all posts View Profile Close tillyfromparadise]

Re: Fat fail

Hi Johnojack,

You can always throw it away but then you have lost $50 worth of methanol
As long as you keep your reactor closed I do not think the methanol is going anywhere soon
The stuff I mixed was quite thick and it readily broke when I added the extra methoxide. Have you tried mixing it? you might be surprised at the results. The most you will lose is 20ml- 30ml methanol and 3.5g NaOH

[Dr Mark Senior Member Find all posts View Profile Close Dr Mark]

Re: Fat fail

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

One further thought on this. If you have an emulsion, a calcium salt may break it. It is of course known that calcium has a very high affinity for traditional soap, which is why synthetic detergents were developed in the first place.

Calcium chloride would be pretty cheap from a chemical supplier (drierite)

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Fat fail

Mark you need to go back and read what I said the problem was in my first post. I don't have an emulsion I don't have any soap I have 90 litres of solid partly converted fat with the consistency of margarine, (from the fridge).
I could heat it over a gas flame but with all the methanol in it that would be foolish. BtW I don't find doing a titration on every batch difficult to do or see it as a chore. Whatever your FRT method is I can't see how it would have compensated for making a simple error with the amount of catylist required.

[Dr Mark Senior Member Find all posts View Profile Close Dr Mark]

Re: Fat fail

Mark you need to go back and read what I said the problem was in my first post. I don't have an emulsion I don't have any soap I have 90 litres of solid partly converted fat with the consistency of margarine, (from the fridge).
I could heat it over a gas flame but with all the methanol in it that would be foolish. BtW I don't find doing a titration on every batch difficult to do or see it as a chore. Whatever your FRT method is I can't see how it would have compensated for making a simple error with the amount of catylist required.

Yes, sorry I didn't read it properly. My method eliminates both titrations and heating. I have two degrees in Chemistry and 30y experience in chemical manufacturing. Thus I make 1000L at a time in an IBC. The link on my website has videos of the process

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Fat fail

Does your non heating method work when making fat into biodiesel? If so please share.

[tillyfromparadise Senior Member Find all posts View Profile Close tillyfromparadise]

Re: Fat fail

Hi Mark,

Originally posted by Mark:
I have two degrees in Chemistry and 30y experience in chemical manufacturing

And yet you continue to deny that the normal single stage base procedure can make biodiesel at room temperature and still claim your procedure is foolproof.

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Fat fail

Finally found some time to have another go at this. Mixed 40 grams of NaOH with 250ml of methanol (would not dissolve in 150ml) and added it to 10litres of 'fat' which I'd warmed up with a couple of small immersion heaters connected in series.
Mixed it like crazy for 10 minutes, seemed to go a bit thinner then left it overnight. Cool this morning and the mix is now gloop, not butter but not biodiesel unfortunately. Should I pop it in the solar heater and see if it separates?

[WesleyB Donating Member Find all posts View Profile Close WesleyB]

Re: Fat fail

If by "fat" you mean tallow or lard, then it might be wet. A formula for sodium soap is fatty acid triglyceride plus sodium hyroxide in the presence of water yields soap plus regenerated water via the saponification reaction. If almost no water is present then you might get more of the transesterification biodiesel producing reaction. It seems to me that 5 grams per litre of sodium hydroxide would be plenty for the transesterification reaction (biodiesel producing reaction mechanism).

[Qwarla Senior Member Find all posts View Profile Close Qwarla]

Re: Fat fail

[QUOTE=Johnnojack;66520]250ml of methanol and added it to 10litres of 'fat'[QUOTE]

With all due respect, Are you just chucking darts at the wall to come up with these numbers?

You would need 2 litres of methanol with 10 litres of oil/fats.