does lye evaporate?

[gregloren1]

im tired of making lye every time. i want to pre-make lye solution for future soap making.

my questions is,
if i make, for example 50%concentrated lye solution with 40oz lye and 40oz water how much water/lye will evaporate ? after lye cools it will weight around 75oz i think.
is it only water that is evaporating ? if only water is evaporating i will add 5oz water to solution and make it 50% concentrated again.

thank you for help

 

[toxikon]

It's called "masterbatching" and is actually very popular! Like you said, just make your 50% lye solution in an appropriate plastic container and make sure it's air tight. Very little if any will evaporate if there's a lid on it.

 

[earlene]

I keep my masterbatched 50% lye solution in an air tight container with a screw-on-lid (#2 recycle code plastic). What might evaporate inside the container, would then condense inside the container and once shaken, reconstitute inside the existing solution (I think because>>>). So far, with weighing using my digital scale, I have not run into any loss of liquid from evaporation.

Be sure to prepare and store in an appropriate container. I use plastic with the #5 recycle code plastic for mixing and store in a #2 recycle code plastic.

Here is a thread addressing masterbatching: http://www.soapmakingforum.com/showthread.php?t=60822

 

[gregloren1]

i understand that it wont evaporate in air tight container...

but do you pour it into container right after mixing lye with water while is still very hot ??
what i meant it can evaporate during/after mising when gets very hot

 

[earlene]

i understand that it wont evaporate in air tight container...

but do you pour it into container right after mixing lye with water while is still very hot ??

No, I let it cool overnight in a larger #5 recycle code container, which also has a lid, so the condensation that does occur from heat changes of the liquid collect and drip back down inside. When cool, I re-weigh the container and compare it to the finished weight from the day before. If there was any evaporation I would add an equal amount of distilled water to make up the difference. In my understanding, any evaporation loss would be water and not actual lye. See this post by IrishLass on the topic of evaporation and adding back water.

what i meant it can evaporate during/after mising when gets very hot

Yes, hence the multiple weights mentioned above. Sorry for not getting what you meant at first.

 

[gregloren1]

if there was any evaporation i would add an equal amount of distilled water to make up the difference. In my understanding, any evaporation loss would be water and not actual lye

thank you !!!

 

[Susie]

I masterbatch mine, and it only loses a tiny amount (1 oz in a 40 oz of NaOH/40 oz H2O) while cooling. This is not enough for me to worry about in the grand scheme of things.

 

[gregloren1]

i have one more question for masterbatchers !

usually i dissolve sugar in my water before lye, but i dont use sugar in all of my soaps.

if i add sugar to cold 50% lye solution it wont dissolve well.. how do you add sugar if you premake lye solution without it??

-during melting oils?
-dissolve in water and add to cold lye (making 33% solution)??

thank you !

 

[Steve85569]

Since you are masterbatching at 50 : 50 you can dissolve sugar in a little distilled water (weighed so you know haw much you are adding) and add that water to the lye the recipe calls for. So if you are making a batch of soap that will use a 2:1 ratio of water to lye you could add that much more water ( half of the weight of water and lye masterbatched) which would give lots of water to dissolve the sugar.

I have not had good luck getting sugar to dissolve in oils. YMMV

Steve

 

[IrishLass]

I master-batch my lye 50/50 and soap my batches @ a 33% lye concentration (2:1 water:lye ratio). When I want to add sugar, I just add it to the extra water I need for my batch.


IrishLass

 

[Susie]

I have my sugar "masterbatched" also, some in aloe vera juice, and some in water. I just make a simple syrup and keep them in the fridge.

 

[gregloren1]

Thank you for replying!
What about tussah silk ?

 

[IrishLass]

I put my tussah silk in my master-batch. It's the only additive I add to it.


IrishLass