Boiling lye no lie

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So I after study decided to add citric acid to my lye. Heated the lye water then added the citric acid so it would dissolve. Then measured and added the lye. WOW.

I have been masterbatching lye for awhile with no issues. But today..whoa..shortly after adding the lye to the citric acid and water it started boiling, bubbled up, then almost as quickly calmed down. I suspect this is because the water was warm and not room temp as is normal for me.

Kind of exciting for a minute before I saw that it wasn't going to boil over and flood my bench.

Lesson learned. Wait till water cools down before adding lye. It dawned on me that lye mixing with water approaches 200 degrees so warm water just might bring things to a boil.

Or I am wrong and you can tell me why. How else can you learn?
 
The boiling point of a 50% lye solution is like ~280 degrees F... as you add the lye to the water, it increases the boiling point of the solution.

I would recommend adding the citric acid to your water before adding lye and then dissolving your lye. You have to go slightly slower, because it will heat up a tad more, but it's not unmanageable.
 
I agree with Obsidian. Acid/Base reaction.

I have only once use CA in soap, and then I mixed the CA with boiling water, and added that to the oils. Then mixed up the NaOH solution. So, go with the answer of someone who actually uses it on a routine basis as to how to perform safely.
 
You can separate out a little water to heat up and dissolve your citric acid in. Once cool, add it to your lye solution.

The boiling was from the chemical reaction between a acid and a base, similar to what happens when mixing vinegar and baking soda.
So you're supposed to heat up water to dissolve citric acid? I always just mixed it with my water before adding the lye and I never had it boil on me either.
 
I do the same--pull off some of the water before adding the lye, and while the lye is cooling, heat the water with my CA and sugar, then dump it into the oil, all ready for the lye solution. I like to mess with the lye as little as possible. I guess my chemistry teachers scared/scarred me!
 
I do the same--pull off some of the water before adding the lye, and while the lye is cooling, heat the water with my CA and sugar, then dump it into the oil, all ready for the lye solution. I like to mess with the lye as little as possible. I guess my chemistry teachers scared/scarred me!
I agree. Today I added the CA to the water to dissolve. I then added the lye to the water. I’m glad I added it slowly otherwise it would have bubbled out on to counter and possibly on me.
 
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