Mixing ASM and KOH.

[dgs]

A while ago I posted a similar thread on VOD where I asked the question;

if the two catalysts are mixed in a 50/50 ratio does the ASM 'consume' the water in the KOH methoxide.

Paul answered but to be perfectly honest it was above most of us to understand, although I appreciate his knowledge of chemistry. His last statement was to say the catalyst would act like AKM, so I don't know if the answer is yes or no. Paul, if you see this maybe you would explain further.

The reasons for doing this are to hopefully produce less soap and to have glycerol that doesn't go solid.

Where I have found a great advantage in using ASM is for the final reaction (say 0.5mls or less dropout on 10/90) where I add the correct amount of ASM without the methanol, seems to work fine and is so much easier.

[Julian]

I've never used KOH, all my experience has been with NaOH and ASM.

I'm lucky to have secured an excellent source of oil recently which usually titrates at less than one.  When using this  oil I use considerably less than the base amount of catalyst and process for longer.

Compared with higher tirtating oil way less soap is generated and so far this Autumn I haven't had any glycerin set solid.  to this end I've started to glycerin wash without problem.

Regarding using ASM to complete reactions, I've been adding it without any extra methanol ever since I started using ASM.  I usually draw of a sample of bio and add the ASM to the sample.  It almost instantly turns yellow and soapy, but I just lob it in the processor via the sight tube and it always seem to work fine.

[dgs]

What about the ASM/KOH methoxide Julian, any thoughts?

The reason i'm a bit concerned about water in the methoxide is this wet methanol I am using up at the moment. Well I assume it's the methanol, I've tested it at @ 0.45% It was the last 400 litres the suppliers had which made me suspicious but I needed it.

My process goes normally until I get to the de-meth stage. Normally glycerol and soap are 'as one' as far as we are concerned, but at the back end of de-mething it seems as if the glycerol (glycerine) splits, leaving the soap as a gloopy brown mess in the bottom of the wash tank. After a couple of hot static washes it is easily removed but I wouldn't stand a chance of just settling with all that mess in the tank bottom.

[Julian]

I've always assumed the soap to be a translucent, milky sort of colour.  I have had many occasions where the soap (or what I'm assuming is soap) has dropped in samples separate from the glycerin (I assumed this was normal).  Also noticed it as the majority of the residue in the settling tank before I started water washing.


0.45% water shouldn't be an issue should it?

If all is normal up to demeth stage, why not try draining the glycerin and demething just the bio followed by water washing.

[dgs]

Thats what I am doing. As the de-meth progresses (by forced evaporation) the glycerine collects at the tank bottom which I run off in stages. As the de-meth continues the glycerine changes to the brown soap, gloopy and sticky. I've never had this happen before but at the moment all the batches do the same.

A batch that I de-methed a few weeks ago had the soap stuck to the tank bottom about 2 inches above the cone and was about 4 inches deep. It was impossible to run it off so I did two hot static washes of 10 litres which dissolved it. The batch water washed normally. I've never had this situation before where during de-mething the soap and glycerine seem to split, Really strange.

[Julian]

Oh, didn't realise you'd drained the glycerin prior to demething just the bio.

"Forced evaporation" is ... heating with no pump running?

Remember I mentioned a brown deposit that drops out of even well washed bio?  Tony and several others have seen it too ... but I think you said you'd never had it.  I notice it mainly in my dispensing tank, may be it could be something similar.

I've always assumed that it's glycerin but I've never been sure.  Like you said a while back we need a forum analyser!

[dgs]

Yes, heating to around 50degs and hard bubbling with the compressor. I stay well away for the 1st hour or so then stop the compressor to drain the glycerol.

I never have any deposits in the bio, no matter how long it stands, even before I centrifuged it. Again to wash I bubble it hard with the compressor, which I would think is very similar to a pump wash. Soap is always 10ppm max.

This recent problem isn't difficult to overcome, but I just find it strange. The nearest thing I can liken the soap to is caramel.

Don't worry, I haven't forgotten about the arduino but the people next door have just moved out (nothing to do with my bio operation) and we have been helping them. They are moving into a smaller house and they had so much stuff that most of it is in one of our barns. One of the removal men said they had "four houses in one" I'm not joking there is so much stuff in there now that we could open an antique shop. They are good friends so we wanted to help them but where it's all going to go?

[DavidShinn]

Plenty of room in the poly tunnel Dave!

[dgs]

Ha Ha,
When the removal men came to asses the scale of furniture next door they said there was four times the amount they expected. they haven't got the keys for their new property so are living in a hotel, Our barn is full of their stuff as is our van, plus a van I borrowed from a friend.

The removal people have put the 1 1/2 wagons of stuff they took in storage until they get the keys, complete nightmare!

Just to think, this little story all started from mixing ASM and KOH.