Author Topic: What have I done? Can't get clear 50/50 pass.  (Read 1577 times)

Offline neisel

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What have I done? Can't get clear 50/50 pass.
« on: November 09, 2015, 12:21:53 PM »
I've been waterwashing a batch since Friday afternoon, at least 20 times & am at my wits end with this one.

Normal 2 stage procedure except I added some acid to break an emulsion which was starting on the 2nd ww (1st after 7% pre-wash).

It looked odd after the 7% pre-wash as there was no discernible soap, that appeared later after several washes. Now I seem to be in cloudy water limbo & it's not getting any clearer. Can't believe there is any soap left, especially as I know I underdosed the 2nd stage, so WTF is causing the cloudiness & how do I get rid of it?

TIA.
« Last Edit: November 09, 2015, 03:14:56 PM by neisel »

Offline julianf

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Re: What have I done? Can't get clear 50/50 pass.
« Reply #1 on: November 09, 2015, 02:38:05 PM »
higher melting point esters, precipitating out with the cold?

mono/di esters?
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Offline neisel

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Re: What have I done? Can't get clear 50/50 pass.
« Reply #2 on: November 09, 2015, 03:18:02 PM »
It's 14 degrees here today & much warmer in the oily shed, don't think the ambient temp is a factor.

After a further 3 w washes it is clear. What a COMPLETE bastard this batch has been.

I'm thinking the problem has something to do with the added acid. It's the only factor which is different from the normal routine.
« Last Edit: November 09, 2015, 09:06:01 PM by neisel »

Offline Manfred

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Re: What have I done? Can't get clear 50/50 pass.
« Reply #3 on: November 09, 2015, 08:11:38 PM »
If you intentionally under dosed the 2nd stage it may be unconverted oil. Even a 10/90 pass is only about 98% or so.

Offline dgs

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Re: What have I done? Can't get clear 50/50 pass.
« Reply #4 on: November 09, 2015, 08:44:22 PM »
neisel, you didn't say if your 10/90 was clear. If there was a lot of soap after the glycerol/water wash you may have produced a lot of FFA's with your acid wash. This could be the cause of your washing problems?

A while ago I intentionally slightly under converted a batch (0.2 mls dropout on 10/90) I water washed it and it did wash OK but the water was never as clear as I like to see it. After finishing the batch I did another 10/90 (optimistically thinking some of the unconverted oil may have been partially emulsified and washed out) still 0.2 dropout.
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