Lye, Citric Acid, and my own stupidity

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i took some distilled water out of my batch water like I did the previous two time with adding diluted CA to my lye solution (this was only my third time using it last night.)

I guess my lye water was still too hot, because when I added the CA/distilled water solution to the lye water it exploded. It was as if you dumped a cup of water into hot oil. I'm ok, I didn't get burned.

But it scared the heck out of me, and now I'm afraid of doing this again.

Was it truly because of the heat of the lye solution to begin with? Or am I doing the whole process wrong?
 
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Yes, boiling when combining lye and acids is a real thing, especially when the lye is warm-ish. I had lye come to an audible boil when it was warm and I sprinkled in solid citric acid.

Acids (citric acid/vinegar/lactic acid/lemon juice, but also the fatty acids in oils) react with lye and liberate heat. With oils (i. e. soap batter), there is much more mass to distribute the heat within, and the reaction is much slower (hours instead of seconds). But it still can get out of control too (volcanoing).

For citric acid etc., better wait until the lye is fully cooled down (patience is well invested here, even when working with masterbatch, since the solution heats up upon dilution!). Then add the acid in small portions and stir thoroughly in between – to keep enough thermal “headroom” for things to not spill over (and for you to react).

Cowards buy/make sodium citrate in advance. ;)
 
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I've done the exact same thing with vinegar by dumping in the lye too quickly. Scary stuff!

If you don't want to wait for the lye solution to cool down, you can do it this way:

1. Make your CA solution.
2. Mix that into the rest of your batch water.
3. Slowly add the NaOH.

OR do it this way:

1. Make your CA solution
2. Mix that into your warm oils
3. Make your NaOH solution separately, then add it to the oils.
4. Since the CA solution has been dispersed into the oils, you won't get the big reaction like you do when mixing the two solutions more directly.

I prefer the first method since I've had the CA precipitate out when it hit oils that were cooler than the CA solution (which I had heated to help the CA dissolve). But either way works. Edited: I realized (per my post below) that I actually use method #2 most often, because I start with master-batched lye most of the time.

I really do prefer using sodium citrate - no lye adjustment, and no lye reaction. Just dissolve in water and go.
 
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Thank you for both responses. I normally add half of my lye to the water, then pop it into the freezer, then add the rest when it clears. Since I put sugar in my water, I am trying to keep the burning down to a minimum when trying to get a nice white soap...but I started realizing that that step is not really necessary.

So this time I left it on the counter to cool without regard to the fact that I am now using CA.. Without thinking about how hot it was, I just poured it into the lye solution. I feel really stupid for not thinking about it, but the fact of the matter is, I am used to it being cool when it is now sitting on my counter, so I got lax and presumed, when actually it was piping hot to begin with. In my mind it should have been cool since it was sitting on the counter.

My first two batches with the citric acid didn't do the explosion, so I can only presume it was because the lye solution was quite cool....but I didn't want to make another assumption about temperature being the culprit because like I said, it was only my third batch doing something that I don't normally do. I had droplets on my glasses, so I am very aware this could have been catastrophic.

I've had spilling lye, dropping cell phone into raw batter type of accidents before...it was really scary with an exploding pitcher.
 

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I use sodium citrate now, but I have always added that or citric acid (dissolved in batch water) by stick blending into my cooled oils. The first thing I do is mix my sugar (added back to the lye solution) and sodium citrate (reserved in a small bowl) in some warmed batch water. I let the sodium citrate (or citric acid) sit while I mix my lye solution and do the rest of the prep work. By the time the lye solution and oils are cool, the sodium citrate solution is at room temperature. I add to the oils and stick blend before adding the lye.

That sounds really scary - I'm glad you weren't hurt.
 
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I use sodium citrate now, but I have always added that or citric acid (dissolved in batch water) by stick blending into my cooled oils. The first thing I do is mix my sugar (added back to the lye solution) and sodium citrate (reserved in a small bowl) in some warmed batch water. I let the sodium citrate (or citric acid) sit while I mix my lye solution and do the rest of the prep work. By the time the lye solution and oils are cool, the sodium citrate solution is at room temperature. I add to the oils and stick blend before adding the lye.

That sounds really scary - I'm glad you weren't hurt.
Good points, @dibbles - I should have mentioned that because I used master-batched lye solution, I dissolve my sugar/sorbitol and sodium lactate (if I'm using it) in my additional water along with the CA or citrate.

I also agree that it's preferable to blend that mix into the oils rather than the lye solution. Otherwise, the additional water causes the lye solution to heat up before it even hits my oils - which defeats the purpose of having premade, room temp lye solution. I should have mentioned that when suggesting option #1 to Kim (in case she was using MB lye), so thanks for helping me remember that! :)
 

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...the additional water causes the lye solution to heat up before it even hits my oils - which defeats the purpose of having premade, room temp lye solution....

I thought you might want to know the same amount of energy is released whether you (1) add the extra water to the masterbatched lye and then add that mixture to the fats or (2) add the extra water to the fats and then add the lye.

There's always X amount of energy released when Y amount of 50% NaOH mixes with Z amount of water.

Because Method 2 releases the heat energy into the fats as well as the lye and water, however, the initial temp rise won't be as high.

But if you use Method 1, once you get that lye and water into the fats and start mixing, the heat energy will be spread out through the soap batter, the temperature rise will moderate closer to what you'd see with Method 2.
 
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@DeeAnna thank you, that makes total sense! The batter is going to do what it is going to do. I do prefer the initial window of working time at the lower temp that I get with Method 2. Maybe it's all in my head, but it feels like it buys me just a bit more time.
 

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i took some distilled water out of my batch water like I did the previous two time with adding diluted CA to my lye solution (this was only my third time using it last night.)

I guess my lye water was still too hot, because when I added the CA/distilled water solution to the lye water it exploded. It was as if you dumped a cup of water into hot oil. I'm ok, I didn't get burned.

But it scared the heck out of me, and now I'm afraid of doing this again.

Was it truly because of the heat of the lye solution to begin with? Or am I doing the whole process wrong?

Oh gosh, I could have written this post.

I recently returned to soap making after a hiatus. I got over my fear of lye. The hardest part is shaking out the little crystals, after that, you're OK by taking proper care.

But I nearly got myself into big trouble. I used ice cubes with a little water for my lye solution because I read that this (a) cuts down on the fumes and (b) cuts down on the amount of time you need to wait to mix into the oils.

After emptying my lye water into my oils, I noticed about a tablespoon's worth of crystals, undissolved, in the bottom of the plastic container of lye water. So I added some water to that & stirred....

I totally forgot that you never add water to lye. Only lye to water.

Nothing happened. (Except the usual reaction where the lye water got hot.) All's well that end's well but not really. I should not have done that.

Can anyone explain why I didn't get an explosion? The lye crystals were undissolved, but wet.
 

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I use sodium citrate now, but I have always added that or citric acid (dissolved in batch water) by stick blending into my cooled oils. The first thing I do is mix my sugar (added back to the lye solution) and sodium citrate (reserved in a small bowl) in some warmed batch water. I let the sodium citrate (or citric acid) sit while I mix my lye solution and do the rest of the prep work. By the time the lye solution and oils are cool, the sodium citrate solution is at room temperature. I add to the oils and stick blend before adding the lye.

That sounds really scary - I'm glad you weren't hurt.

I added sodium citrate to lye solution. Nothing happened. Did I do something wrong?
 
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I added sodium citrate to lye solution. Nothing happened. Did I do something wrong?
Not really wrong per se, but once you have added NaOH to the water, it's hard to get anything else to dissolve, especially if you are using a high lye concentration, aka low water. That's the primary reason it's suggested that you dissolve all additives first, before adding the NaOH, or that you separate out some of the batch liquid just for dissolving additives. Either way will get the job done.

I totally forgot that you never add water to lye. Only lye to water.
Nothing happened. (Except the usual reaction where the lye water got hot.) All's well that end's well but not really. I should not have done that.
Can anyone explain why I didn't get an explosion? The lye crystals were undissolved, but wet.
There wasn't enough lye to create a problem. I personally don't know just how much lye is needed to create the explosive reaction (and don't plan to find out) but I have scraped out small amounts of lye with a wet or damp utensil, and nothing bad happened.
 
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Not really wrong per se, but once you have added NaOH to the water, it's hard to get anything else to dissolve, especially if you are using a high lye concentration, aka low water. That's the primary reason it's suggested that you dissolve all additives first, before adding the NaOH, or that you separate out some of the batch liquid just for dissolving additives. Either way will get the job done.

There wasn't enough lye to create a problem. I personally don't know just how much lye is needed to create the explosive reaction (and don't plan to find out) but I have scraped out small amounts of lye with a wet or damp utensil, and nothing bad happened.

1. Thanks for clearing up the order of operations. I'll remember that for next time but I do think that my SC dissolved - I added too much (1 tsp for a 1/2 lb batch) and I got a pudding like trace w/an 80% EVOO oil mix after only 3-4 minutes of stick blending. But next time I'll do better (& add less SC).

2. Again, thanks. Still, I'm annoyed at myself. Working with lye is the only thing that's ever daunted me about soaping and realizing in retrospect that I broke a cardinal rule is exasperating. I thought I wasn't one of those people*. Well, I am.

I think part of the problem was that my lye water was mostly made up of ice cubes. I didn't start out with a 50/50 mix. So, some of the lye melted the ice cubes but there wasn't enough water to melt the lye crystals. There has to be enough water for there to be a full reaction. Ice water is one thing; all ice is another.

*Careless
 
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3-4 minutes of stick blending is what made your soaps like pudding. Trust me...you watch the you tube videos and think that's what you are supposed to do. But they are making huge batches. I do zzzzing, zing (check), zing zing (check). In short bursts for less than a minute total. I keep my batter pretty fluid for designs. And most of it is with a spatula just stirring. If I were just doing one color I would still keep it to less than 30 seconds in 10 second bursts.

You are doing zzzzzzzzzzzzing for three minutes. Way too much, even for an olive oil soap.

Edit...I had my hand slapped quite a few times here on my sb. Just do a little and stir a lot just to see where you need to be. Then zing all you want to get where you need to be. I made soap tonight. I kept everything fluid, then zapped the crap out of one stubborn pitcher to get it up to speed.
 

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3-4 minutes of stick blending is what made your soaps like pudding. Trust me...you watch the you tube videos and think that's what you are supposed to do. But they are making huge batches. I do zzzzing, zing (check), zing zing (check). In short bursts for less than a minute total. I keep my batter pretty fluid for designs. And most of it is with a spatula just stirring. If I were just doing one color I would still keep it to less than 30 seconds in 10 second bursts.

You are doing zzzzzzzzzzzzing for three minutes. Way too much, even for an olive oil soap.

Edit...I had my hand slapped quite a few times here on my sb. Just do a little and stir a lot just to see where you need to be. Then zing all you want to get where you need to be. I made soap tonight. I kept everything fluid, then zapped the crap out of one stubborn pitcher to get it up to speed.

You're right - I looked at YT vids beforehand to refresh my memory and yes, they always stick blend the hell out of batters. Interestingly, in the past I've had batters that didn't turn to pudding and the soaps came out OK. I didn't do a design so it doesn't matter re the soap but it'll save my blender so I'll blend less in future. Thanks.

I'm still annoyed at myself for being so thoughtless. That's how accidents happen.
 
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3-4 minutes of stick blending is what made your soaps like pudding. Trust me...you watch the you tube videos and think that's what you are supposed to do. But they are making huge batches. I do zzzzing, zing (check), zing zing (check). In short bursts for less than a minute total. I keep my batter pretty fluid for designs. And most of it is with a spatula just stirring. If I were just doing one color I would still keep it to less than 30 seconds in 10 second bursts.

You are doing zzzzzzzzzzzzing for three minutes. Way too much, even for an olive oil soap.

Edit...I had my hand slapped quite a few times here on my sb. Just do a little and stir a lot just to see where you need to be. Then zing all you want to get where you need to be. I made soap tonight. I kept everything fluid, then zapped the crap out of one stubborn pitcher to get it up to speed.

Your description of stick blending had me laughing at my desk here at work. Hilarious but perfect. Now every time I'm going to be stick blending I will be thinking zzzzing. LOL
 
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I think part of the problem was that my lye water was mostly made up of ice cubes. I didn't start out with a 50/50 mix. So, some of the lye melted the ice cubes but there wasn't enough water to melt the lye crystals. There has to be enough water for there to be a full reaction. Ice water is one thing; all ice is another.
Many people successfully use 100% frozen liquid, whether goat milk or ice cubes. The key is not to add all the lye at once, but to add a bit, stir to dissolve, add a bit more, stir to dissolve, and so on till you are done. If you want to see it done in bulk, there is a fun YT video where one soaper pours 50 lbs of ice into a huge SS pot, and then proceeds to pour NaOH from huge bags onto the ice. That's how she makes her MB lye solution.
 

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Many people successfully use 100% frozen liquid, whether goat milk or ice cubes. The key is not to add all the lye at once, but to add a bit, stir to dissolve, add a bit more, stir to dissolve, and so on till you are done. If you want to see it done in bulk, there is a fun YT video where one soaper pours 50 lbs of ice into a huge SS pot, and then proceeds to pour NaOH from huge bags onto the ice. That's how she makes her MB lye solution.

That, too, was my problem - I didn't sprinkle. I dumped. Also dangerous. It was such a small amount, so no harm - but still, not good lye technique. I really had a phobia about lye. I think I have the technique down now.

The only problem is that sometimes the crystals clump in the container. So I squeeze and shake the container around to de-clump. Not 100% effective, but it mostly worked.
 
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If the crystals are clumping in the container, it's likely that the container was not airtight, or at least, not fully sealed. This also weakens the lye, so be sure you are keeping it airtight. :)
 
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