i found a lot more emulsified product than i thought was in there - close to 15 gallons and now i have no idea what to do. I have some of it in a 10 gallon drum with an immersion heater in it and the rest in a 5 gallon bucket and i just put some salt in it.
I can't find anywhere on line how much salt to add, or how much glycerin to use if i were to try that.
Any idea how i could get some biodiesel out of this white emulsion?
thanks,
Paul

I think the general rule of thumb is keep adding it until it has just broken.

When you wash it the stuff you have added will all wash out as normal.

What did you do to get such a mess? over vigorous washing? The first wash should be VERY gentle as this is the wash that gets rid of most of the soaps. The soaps stabilize the emulsion but wash out very easily even with a gentle wash.

Maybe try to do less with your first wash? Even static washing will eventually do the job.. maybe 24 hours just standing on top of some warm water to start with then drain and wash again in future? That prob won't help once a stable emulsion has already formed though.

Try this http://riodiesel.com/bd/rnd/emulsion.php

-Jack
http://riodiesel.com/

thanks for the help!
i think one problem is that the walmart double-outlet aquarium pump (used with a grinding wheel as a bubbler) is actually too powerful for my 30 gallon wash tank. I had a feeling that the bubbling action seemed a bit aggressive, but i know a lot of other people are doing the same thing so i did not worry about it.
After a static first wash i then changed the water and bubbled overnight with this thing which is probably what caused the main problem -bubbling too much the first time.
Does this make sense to anyone?

Finally what i did was run to the hardware store and buy a needle valve to insert after the aquarium pump, and i found that opening the valve just the slightest amount possible created a good amount of bubbling - and when i opened it all the way it really seemed too forceful so i left it open only a tiny bit.
hopefully this will do the trick, meanwhile all the emulsified stuff seems to be very slowly settling out in another container.
thanks,
Paul

The next time you process a batch, pump it into the emulsion and it will break. Hot glycerol works wonders!

Paul

best emulsion breaker I have used is Jack Jones glycerine method (link in Jack's post above), try it, you will never worry about making emulsion again.

Chug

I have not tried the Jack Jones method as it seems to have a fundamental flaw. The presence of an alcohol (glycerine) is supposed to account for its efficacy. Consider, though, that there is already an alcohol (methanol) in the esters being washed. If there is a problem being solved here, the mechanism is not explained in the method write-up.

I suggest you try it on a small sample. If it doesn't work no harm is done and there are other proven methods. If it does work it doesn't matter why it works but it would be interesting to find out and someone is sure to post some theories in the end.

i have been trying the glycerin method on smaller samples and noticed something really strange about it just today:
i took a mason jar filled with white emulsified stuff and added a good amount of glycerin and in about an hour i found that there was a clear layer of seperated water (dark from the glycerin) in about 75% of the jar, while the top part was still the white emulsion. After several hours it is still like that and i noticed the same thing on larger samples.
It seems like it seperates a lot of water out but leaves a layer of emulsion with no clear layer of biodiesel.
What am i doing wrong here?
Paul

quote:

Originally posted by David L. Teal:
I have not tried the Jack Jones method as it seems to have a fundamental flaw. The presence of an alcohol (glycerine) is supposed to account for its efficacy. Consider, though, that there is already an alcohol (methanol) in the esters being washed. If there is a problem being solved here, the mechanism is not explained in the method write-up.

David,

I'd sure be interested in your theory as to why this method works. Are you a chemist?

I do have to correct one thing; there may be what was once a methanol molecule in the biodiesel ester but it is no longer a methanol molecule, it is part of an ester. In fact it resembles a methane molecule more then a methanol molecule at the ester stage. It behave quite differently from an alcohol because it is part of a bigger (different) molecule...the ester.

However, there is methanol in the biodiesel by-product and my theory is that the methanol and glycerin in the by-prodcut are responsible for lowering the surface tension of the emulsified biodiesel allowing the biodiesel to break free. It's a very similar process to when I make transparent soap. I add alcahol (preferably ethanol) and glycerin to the saponified oils to break up the soap crystals.

-Jack
http://riodiesel.com/ a.k.a. http://RiverstonesBiodiesel.com/

quote:

Originally posted by GREASE FIRE:
i have been trying the glycerin method on smaller samples and noticed something really strange about it just today:
i took a mason jar filled with white emulsified stuff and added a good amount of glycerin and in about an hour i found that there was a clear layer of seperated water (dark from the glycerin) in about 75% of the jar, while the top part was still the white emulsion. After several hours it is still like that and i noticed the same thing on larger samples.
It seems like it seperates a lot of water out but leaves a layer of emulsion with no clear layer of biodiesel.
What am i doing wrong here?
Paul

Paul,

Are you heating the emulsion or the by-product? It really has to be close to 90F to work, hotter is fine too. After adding the by-product are you mixing them? A good mix but don't go crazy, too strong of a mix will just make more emulsion. After the emulsion is broken the biodiesel layer is not clear, in fact it's pretty dark and kinda difficult to see the difference between the water/by-prodcut layer and the freed biodiesel without good lighting. Can you post pictures?

-Jack
http://riodiesel.com/ a.k.a. http://RiverstonesBiodiesel.com/

My final year research project at university involved producing liposomes containing water droplets, very much like happens in emulsion formation although using a chemical rather than mechanical method of producing them.

We had various ways of bursting them:- Physically by sonification or repeated freeze/thaw cycles or chemically by either

i) changing the osmotic balance around the droplets
ii) introducing surfactants to disrupt the membranes.

At a guess I would say that both of the above mechanisms are involved in the glycerine emulsion busting method. Predominantly though it will be the increase in ionic molecules disrupting the soap membranes. You can keep adding it for a while but eventually there just isn't enough free soap left to maintain the liposomes.

Grease Fire, If all else fails you could go back to salt. Dissolve 1% salt in 5% water. Heat stir and settle. Then separate and wash very gently with water.

why adding glycerine works:

my guess--and i am a chemist, though this is far from my area of study--is the the adding glycerine increases the specific gravity of aqueous layer and thus provides more driving force for phase seperation. (s.g. of glyc is like 1.2) also, all the NaoH or KOH that you add to get the raction going ends up in the glycerine, so the glycerine ought to have a high ionic strength. so adding glycerine to the emulsion is a lot like adding salt to an emulsion....

Did you test the wvo for the presence or amount of water prior to the primary reaction? If not, that could be the driving force behind the tendency to produce all that gook.

I know that doesn't make your gook go away, but it might prevent the next batch of gook from happening.

Finest regards,

troy

Troy,
so are you saying that if the wvo has water in it the main reaction can still go fine but it will cause emulsions during the wash stage?

I was not aware of that - i just thought water would mess up the main reaction if it was there.
Anyway the wvo is used was pretty good, could not have been much moisture in it but i can't say for sure there was none. I will have to be more careful to check this next time.
thanks,
Paul

quote:

Mesuno

Mesuno and tupper I'm going to add your comments to my emulsion busting page at http://www.riverstonesbiodiesel.com/bd/rnd/emulsion.php

If you have any objections let me know and I'll remove the comments from my site.

-Jack
http://riodiesel.com/

I've had the same emulsion problems that GreaseFire has experienced. The static wash on heated water goes fine. Even two times. Then, even seemingly mild bubbling causes emulsion. Same with mild misting.

As for emulsion busting, I just dump in some dark glycerine byproduct and it clears up within 24 hours. Has worked great for me three times now. (thanks, Jack)

I've about had my fill of washing and dealing with emulsions Perhaps others have figured out how to avoid them, but despite my careful efforts they persist.

The other great threads going have reassured me that unwashed biodiesel won't wreck my life or the injection pumps in my 78 240D or 95 F350. After this batch I'm going to make the switch

Cheers,
Eric

[QUOTE]Originally posted by GREASE FIRE:
Troy,
so are you saying that if the wvo has water in it the main reaction can still go fine but it will cause emulsions during the wash stage?"

Yes, that is exactly what I am saying. Large amounts of water can kill the main reaction, but modest amounts may produce "good looking" biodiesel with normal separation of byproduct. But the biodiesel can have so much soap in it, that settling or washing can both be problematic and/or very time consuming, if not impossible.

And testing for water is easy, so why not?

Good luck and have fun!

troy

Water in WVO doesn't stop the reaction, but it does rob NAOH from it, so it ends up under-reacted AND soapy - a bad combination. Under-reacted BD has more mono- and di-glycerides, which are emulsifiers. Combining emulsifiers with soap, then trying to wash them out can be very difficult.

I recently tried a brute-force method on an emulsion that had persisted for a year. I heated it (in my "bird-waterer" wvo drying rig) to 250F. It came out perfectly clear and nothing has settled out since!! I'll try an Idaho test (shake with 1:1 ratio water), but I want to try re-reacting it to see if it's actually a stabile blend of BD, mono-glyceride, di-glyceride and (dry)soap.