Reprocessing with HMPEs

[Head Womble]

Is it me or does this suggest that HMPE's are a form of reverse reaction.

We know non titration followed by WBD produces an excess of HMPE's,
so does using less catalyst (non titration) produce a marginal reaction, that can be, to some extent,
reversed if then heating for extended time at high temp (WBD).

Could it be that the esters are not properly bonded together, so are easier to split the methanol molecule from them,
but still bonded enough to pass a 27/3 test.

I'm no chemist, so this is only what my simple mind has come up with.

[Dickjotec]

Given the (apparently) HMPE problems I had with the acetone batch that I did not WBD it will be interesting to see how the next one that I intend to WBD turns out.
Dick

[Jamesrl]

Is it me or does this suggest that HMPE's are a form of reverse reaction.

I mooted just that point quite some time ago.

[Carrington]

this is why i think we need to remove any remaining catalyst from the batch before we do wbd
it is still my theory that after we get a complete reaction and then go onto demeth that any remaining catalyst will carry on doing the job the we employed it to do which is to remove the alcohol from the fatty acid, when it has done this if there is any glyc remaining in the product then as there is three entry points on the glyc molecule then it is far easy er for the glycerin  molecule to re-bond with the fatty acid. the product phase that has glycerin re-bonded will become much more hygroscopic which becomes a problem in cold weather.
if anyone out there does a 5% water wash after reaction and then goes onto wbd would you be interested in trying something to maybe help with this.
if so send me a message and i will send you something to try.

Paul

[nathanrobo]

this is why i think we need to remove any remaining catalyst from the batch before we do wbd
it is still my theory that after we get a complete reaction and then go onto demeth that any remaining catalyst will carry on doing the job the we employed it to do which is to remove the alcohol from the fatty acid, when it has done this if there is any glyc remaining in the product then as there is three entry points on the glyc molecule then it is far easy er for the glycerin  molecule to re-bond with the fatty acid. the product phase that has glycerin re-bonded will become much more hygroscopic which becomes a problem in cold weather.
if anyone out there does a 5% water wash after reaction and then goes onto wbd would you be interested in trying something to maybe help with this.
if so send me a message and i will send you something to try.

Paul

You're brave, casting aspersions on the sacred WBD!  I thought that questioning this process or making any suggestion that problems were connected with it was viewed as heresy or at least very taboo

[Tony]

Not here it ain't 

Paul I don't think anyone does 5% water followed by WBD as that ruins the recovered Methanol purity.

Perhaps acid neutralisation prior to WBD would work, but how do we do that without adding water too?

[Julian]

I've tried that.   You add concentrated Sulphuric to Methanol to neutralise the soap, after which you go and change your underpants.

Seemed to work ok but I wasn't happy doing it!

[Jamesrl]

I've tried that.   You add concentrated Sulphuric to Methanol to neutralise the soap, after which you go and change your underpants.

Surely taking a safety minded approach to the problem with the addition of the correct PPE would be best.

May I suggest the addition of Incontinence Pants, they'll take away the worry of sh!ting yourself during the process.

Be Prepared and safe out there.

[Julian]

I've tried that.   You add concentrated Sulphuric to Methanol to neutralise the soap, after which you go and change your underpants.

Surely taking a safety minded approach to the problem with the addition of the correct PPE would be best.

May I suggest the addition of Incontinence Pants, they'll take away the worry of sh!ting yourself during the process.

Be Prepared and safe out there.

He, he, like it.

Perhaps we should add IP to the acronyms list ... we could do a wiki page!

I was careful and did wear wraparound goggles.  But I find working in rubber gloves  more dangerous than without, you seem to have far less control over what you're doing (waiting for comments on that one).

PS ... Jim there's no swear filter on here.  There's not really been a need, the odd bit of mild and controlled bad language hasn't raised any hackles ... yet!

[Tony]

Incontinence pants?  Talk about overcomplicating things, what's wrong with a cork?

It is curious that my attempts to water wash HMPEs have left a white band in the middle very similar to the band seen in Dick's photos of the cream from the top after using Acetone.  I suspect they are the same thing.

Perhaps it's not HMPEs but soap somehow bound up with FAME?

[Dickjotec]

Don't think it is soap as it does not mix with water but separates out.
I did an experiment today that was interesting? I have a jar of old HMPE so I did a 50/50 and not surprisingly got a white layer over water. I then added acetone shook and the white layer got bigger! I intend to try some more tests but only have 1 test tube so I am waiting for some to be delivered.

Could it be mono or di glyc!

Dick

[Carrington]

I think you are right dick , I think it's made up of all mono's . This then suggest a back reaction or the 09/10 test isn't really big enough as the original test was 225/25.
I think for the near future I'm going back to 225/25 until we can prove that it's a back reaction

Paul

[Tony]

That would make sense as they are great emulsifiers.  And would therefore wash out.

But why would their melt point be up in the 50-60C range?

[julianf]

Have a look at this link -

http://www.rikenvitamin.jp/int/emulsifier/spec/dmg.html

I have not looked at it much, but it certainly supports elevated melting points.


As a side note -

I deliberately overdose the 2nd stage of the 2stage no titration.  I figure i can accept the extra soap from a 10% overdose on 10% (or whatever) of the batch.  This, i assume, pushes things to a true 100% conversion, however, i have not yet concluded what may happen to the excess catalyst!

[nathanrobo]

Have a look at this link -

http://www.rikenvitamin.jp/int/emulsifier/spec/dmg.html

I have not looked at it much, but it certainly supports elevated melting points.

That's interesting...

If they are fats, why do they not convert in the process?  If it's that we have a conversion of 99.XX% with the unconverted not detected by 10/90 there's no reason why it would all have a high melting point unless the following is the case:

1. There is oil present in the bio, which doesn't show up - but this stuff does due to it's higher melting point
2. Or if the fats are less likely or harder to reach 100% conversion (so if you have 95% oil for example and 5% fats in your feedstock, all of the oil goes over but only a % of the fats.

As Paul says it could be Mono's... If mono's do they have properties that would mean higher melting points.

Another question for consideration is... Are all of what we're referring to as HMPE's or waxing stuff, are they always the same or could there be a number of elements that appear to have the same properties.

Too many questions!