Soaps/Acetone

[nathanrobo]

B good if a chemist type could chime in and define this.  Bio often pre-neutralisation has a high PH due to the presence of lye?  Soaps are present due to the neutralisation of ffa - all agreed about this! These soaps still exist after neutralisation, this shouldn't be too controversial!

Err, I think you may have the wrong idea as to what the lye does. It's a catalyst.

A catalyst is NOT consumed in the reaction but the lye over the base number is used to neutralize the FFA in the WVO which results in soap.

The converted and finished bio should be Ph 7, be it water washed to remove the soaps or demethed and settled.

Adding Acid to to the wash water neutralizes the soaps mono and di-glycerides.

As you say Jim the catylist is not consumed so therefor is still available to make soap if water is added , by adding acid this then kills the catylist preventing it from being able to create soap when water is added.
The bio should be ph7 as the catylist doesn't disolve in the oil or bio but it still floats about in the mix until washed or settled out
So the bio is ph7 but the mix could be up as high as 12-14

Paul, that seems in line with what I said, or did I miss something?

[Carrington]

Sorry Nathan I just read the last post by Jim when I posted
You got it

[Head Womble]

B good if a chemist type could chime in and define this.  Bio often pre-neutralisation has a high PH due to the presence of lye?  Soaps are present due to the neutralisation of ffa - all agreed about this! These soaps still exist after neutralisation, this shouldn't be too controversial!

Err, I think you may have the wrong idea as to what the lye does. It's a catalyst.

A catalyst is NOT consumed in the reaction but the lye over the base number is used to neutralize the FFA in the WVO which results in soap.

The converted and finished bio should be Ph 7, be it water washed to remove the soaps or demethed and settled.

Adding Acid to to the wash water neutralizes the soaps mono and di-glycerides.

As you say Jim the catylist is not consumed so therefor is still available to make soap if water is added , by adding acid this then kills the catylist preventing it from being able to create soap when water is added.
The bio should be ph7 as the catylist doesn't disolve in the oil or bio but it still floats about in the mix until washed or settled out
So the bio is ph7 but the mix could be up as high as 12-14

So I was right in thinking that the titrated soap test is effected by the acid wash, as it works on PH value.

This will be why my soap tests have shown low ppm even on the unwashed sample.

So the only soap test that will truly show accurate results is the 50/50 test (which isn't accurate) 
I know I can use a Lazar pen but this still doesn't produce a quantifiable figure.

I'll just have to do my next batch without the acid wash so I can get accurate results for the "use of acetone to remove soaps" page.

[Head Womble]

B good if a chemist type could chime in and define this.  Bio often pre-neutralisation has a high PH due to the presence of lye?  Soaps are present due to the neutralisation of ffa - all agreed about this! These soaps still exist after neutralisation, this shouldn't be too controversial!

Err, I think you may have the wrong idea as to what the lye does. It's a catalyst.

A catalyst is NOT consumed in the reaction but the lye over the base number is used to neutralize the FFA in the WVO which results in soap.

The converted and finished bio should be Ph 7, be it water washed to remove the soaps or demethed and settled.

Adding Acid to to the wash water neutralizes the soaps mono and di-glycerides.

As you say Jim the catylist is not consumed so therefor is still available to make soap if water is added , by adding acid this then kills the catylist preventing it from being able to create soap when water is added.
The bio should be ph7 as the catylist doesn't disolve in the oil or bio but it still floats about in the mix until washed or settled out
So the bio is ph7 but the mix could be up as high as 12-14

Come on Mark spit it out lad !

Edited, please read again.

[1958steveflying]

B good if a chemist type could chime in and define this.  Bio often pre-neutralisation has a high PH due to the presence of lye?  Soaps are present due to the neutralisation of ffa - all agreed about this! These soaps still exist after neutralisation, this shouldn't be too controversial!

Err, I think you may have the wrong idea as to what the lye does. It's a catalyst.

A catalyst is NOT consumed in the reaction but the lye over the base number is used to neutralize the FFA in the WVO which results in soap.

The converted and finished bio should be Ph 7, be it water washed to remove the soaps or demethed and settled.

Adding Acid to to the wash water neutralizes the soaps mono and di-glycerides.

As you say Jim the catylist is not consumed so therefor is still available to make soap if water is added , by adding acid this then kills the catylist preventing it from being able to create soap when water is added.
The bio should be ph7 as the catylist doesn't disolve in the oil or bio but it still floats about in the mix until washed or settled out
So the bio is ph7 but the mix could be up as high as 12-14

So I was right in thinking that the titrated soap test is effected by the acid wash, as it works on PH value.

This will be why my soap tests have shown low ppm even on the unwashed sample.

So the only soap test that will truly show accurate results is the 50/50 test (which isn't accurate) 
I know I can use a Lazar pen but this still doesn't produce a quantifiable figure.

I'll just have to do my next batch without the acid wash so I can get accurate results for the "use of acetone to remove soaps" page.

The way I see it is using acid has simply reduced extra soap production in the first place. Your tests still show whether using Acetone gets the soaps out quicker, all be it less of them so still very helpful and a good comparison.

[Head Womble]

I agree it still shows good results from the method, but they're not quantifiable.

Doing it without the acid wash will be, also it'll be good to prove the method works without the acid wash,
showing it's more versatile.

[Jamesrl]

I've just finished my second 100ltr batch using Acid and Acetone, this time I added 2ml/ltr to the first Titrated Acid (80ml H2SO4) wash water.

1st wash was 10ltr run for 1hr and settled over night.

2nd wash just 10ltr of water washed fro 30mins and settled for a couple of hours.

A 50/50 soap test after the second wash showed crystal clear water, I gave it a 3rd wash just to make sure though, it's now drying in the reactor using the condenser and water is flowing nicely at only 60°C, y'can beat a squirrel for rapid evaporation.

[1958steveflying]

I've just finished my second 100ltr batch using Acid and Acetone, this time I added 2ml/ltr to the first Titrated Acid (80ml H2SO4) wash water.

1st wash was 10ltr run for 1hr and settled over night.

2nd wash just 10ltr of water washed fro 30mins and settled for a couple of hours.

A 50/50 soap test after the second wash showed crystal clear water, I gave it a 3rd wash just to make sure though, it's now drying in the reactor using the condenser and water is flowing nicely at only 60°C, y'can beat a squirrel for rapid evaporation.

It certainly does seem to have at least halved the washing that used to be required, are you finding reduced HMPE's now your washing Jim ?

[jgs600]

so you added 2ml per litre of acetone with the first acid wash..correct or did you do an acid wash first then add the acetone in with the second wash... just to be clear here..

got my asm now so cant wait to do my forst batch..

[Jamesrl]

[quote author=1958steveflying link=topic=860.msg9474#msg9474 date=1360529840

It certainly does seem to have at least halved the washing that used to be required, are you finding reduced HMPE's now your washing Jim ?
[/quote]

I can't really comment of the reduction of washes as these last two batches are the first I've ever washed.

As for HMPE's I haven't really suffered since I've been using the titless method with ASM, I've had the odd batch with a few but nothing serious.

Glenn, yes I did add 2ml/ltr to the first acid wash water, worked for me.

[nathanrobo]

So... what du think?  will you continue with the water?

[Jamesrl]

So... what du think?  will you continue with the water?

Mmmmmmmmmmm! To be honest I think it's a complete PITA, what used to take me  less than an hour hands on over one evening now takes a two days and a lot more intervention and power.

The only advantage I can see is if you can devote the time over a weekend you'll have fuel for Monday morning as against having to wait several days for settlement.

[nathanrobo]

So... what du think?  will you continue with the water?

Mmmmmmmmmmm! To be honest I think it's a complete PITA, what used to take me  less than an hour hands on over one evening now takes a two days and a lot more intervention and power.

The only advantage I can see is if you can devote the time over a weekend you'll have fuel for Monday morning as against having to wait several days for settlement.

Fair comment! 

[Head Womble]

That's really good news Jim, both you and Jules have had similar results to me.

This has spurred me on to get the next batch done once my meths gets here,
it's semi solid wet gunk that will need drying before the gly wash,
so should be a good test batch with interesting results.

I know it's no good for this time of year but I need to get some of my collection drums emptied.
Once it's done I'll pump into a 220L drum ready for the warmer weather.

[Head Womble]

I have finished another batch, it wasn't a full batch semi solid wet gunk but around 25%, 75% good liquid oil.

I had problems with the reaction and had to do a third stage to get a good pass (oil not as dry as it could have been)
this meant there was more methanol left in the bio and higher amounts of soap produced.

It was acid washed (I knew this batch was not going to be good for test results), then an acetone wash.

The acetone wash did not work as well as previous batches, and the washwater still smelt of meths.

So looking back at the other batches that were non titration two stage with 16% meths, I think it's more effective when methanol and soap levels are reasonably low.
This I think is backed up by the results Julian had recently.

I'm going to try demething before washing as I think this will help with soap removal.