# Storing lye water



## Sanguine

Hii,
I was wondering if you can store lye water in the fridge. Or any other type, with milk, wine, beer,...
In hp or cp i wouldnt be bothered storing it, but when making whipped soap, chilled lye is wanted.
It takes a few hours to chill lye water, what if for whatever reason you cant make the soap that day or the following days... Can you store lye water?

Thanks in advance!

Edit: sorry, just noticed that i'm in the wrong part of the forum..


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## Lindy

Hey there.  Put a cover on your lye and you can store it where-ever you would like just make sure you label it well.


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## Sanguine

Thank you!
How long do you think it can be stored this way?


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## green soap

Indefinitely, or a very long time.  Some folks master-batch their lye.


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## IrishLass

I masterbatch my lye all the time and it lasts seemingly forever. The longest I've stored a single batch of my lye solution so far was for about 8 or 9 months (at room temp), and it was still in perfect soaping condition. I make my masterbatch with 50/50 water to lye ratio (with added silk).

IrishLass


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## Maythorn

I guess I'm too afraid to ever have lye water or soap tools, containers and spoons anywhere near food.  Even when I put a log in the freezer for a few minutes to cool it down for not-gelling I always wipe the freezer floor down with a sponge after and the door hande because I've touched the outside of the mold with gloves that might have some raw soap on them.

That's interesting about lye water strength staying intact, though over time.  I thought like anything else it would weaken eventually.


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## LuvOurNewf

IrishLass said:
			
		

> I masterbatch my lye all the time and it lasts seemingly forever. The longest I've stored a single batch of my lye solution so far was for about 8 or 9 months (at room temp), and it was still in perfect soaping condition. I make my masterbatch with 50/50 water to lye ratio (with added silk).
> 
> IrishLass




Quick question on your masterbatch. I too have tried this but after I use it a few times I notice that it forms crystals on the spout. I always wipe the spout off. When I pour it the consistency seems thick and has flakes in it. I always shake the container prior to use to mix it after it's been sitting for a while, 2 months is the longest I've gone, but I still gets flakes.

Is this normal?


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## IrishLass

When you make your 50% solution, I've found it helps tremendously to account for the water loss that occurs as you are mixing it up. The first time I made mine, I weighed everything before and immediately after mixing- including the mixing container and cover- in order that I could determine how much water evaporated off as I was mixing. It turned out that I had a water loss of 6 grams. I added that back in, placed the cover on and waited for it to cool off. Once cooled off, I weighed it again to make sure no more water had evaporated off (all was well). Then I pour it through a stainless strainer into my storage container.  

The next time I mixed up a batch of 50% solution, I weighed out 6 grams extra water at the beginning, and when I weighed it at the end of mixing, it was a perfect 50% solution. Since then, I've made all my subsequent batches of solution with a 6 gram excess of water at the beginning and it all surprisingly evens out to a perfect 50% solution at the end. Just weigh everything before and after to find out how much water you're losing and add it back in when done mixing. And then doublecheck when it has cooled off.

It's normal for a 50% solution to be somewhat thick/syrupy (I'd actually be concerned if it wasn't). It shouldn't have flakes, though. If it does have flakes, it could be any of these things: Your mixing or storage container had some soap residue in it and the lye has reacted with it to form harmless soap flakes; it might be harmless sodium carbonate that has formed from the lye in the solution reacting with air (it doesn't dissolve, but can be strained out); it could be that the solution has gotten too cool and the lye has precipitated out (applying a little heat will remedy that); or there wasn't enough water present for the lye to stay mixed properly (just add a little more water).

As for flakes forming on the spout, this happens to me, too, but I've noticed they dissolve when mixed back into the solution. I usually see a few flakes on the cover to my container, too, and I've noticed that as the cover sits on my counter during the time it takes for me to weigh out my needed amount of solution, the flakes on the cover turn into liquid. That's because lye is very hygroscopic (attracts moisture in the air to itself). 


HTH!
IrishLass


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## LuvOurNewf

IrishLass,
             Thanks for all the useful information. I will absolutely follow your lead with weighting, weighting and re-weighting. I know the solution gets hot but never thought about how much evaporation there may be. As a matter of fact I'm on my way to put this into practice.
Thanks again.


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## FaeryKiss

*container for lye water*

Hi all, I want to master batch my lye water and unsure how to start. I am not sure what kind of container to store it in. I have been making cp soap for years and want to try room temperature soap. Thanks!


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## MzMolly65

bumping an old thread rather than starting a new one.

I want to masterbatch some lye water too and I have a # 2 container with a screw on lid, will that be adequate to store a 50/50 solution?


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## MzMolly65

bumpity bump bump ... still hoping for an answer


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## Lindy

Is it dishwasher safe?  If it is then I think it would be fine for lye.  That's the rule of thumb that I go by.  I don't know what mine is (it's full of lye and I kinda don't really want to look at the bottom IYKWIM) but I did buy it at the dollar store so it's pretty cheap plastic and I haven't had any problems.  It flexes when I add the lye into the water from the heat but it holds up and that's what's important.


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## Tienne

To store a strong NaOH solution, you should keep it in a container made of polyethylene. Never use a container made of *PC or *PETD plastic;

"_Immediate damage may occur. Depending on the plastic,  the effect may be severe crazing, cracking, loss of strength,  discoloration, deformation, dissolution or permeation loss.

_http://www.calpaclab.com/Chemical-Compatibility-Chart-s/789.htm


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## new12soap

HDPE with the recycle code "2" (inside the triangle thing), like a thoroughly rinsed out laundry detergent or fabric softener bottle should be fine.


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## cmzaha

I use a number 2 hdpe with a safety cap for my lye solution, but I do not pour it in the bottle hot.


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## Lindy

I actually make mine right in the container...  But it is like a container with a lid that has a hole and cap for pouring.


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## cmzaha

Lindy, how do you get it mixed well enough? I find I have to stir my 50/50 lye solution a lot to make sure it is fully dissolved? I also do not always trust the heat from mixing a gallon at a time in hdpe bottles. My #2 hdpe buckets get pretty soft when I mix a gallon at a time, which is why I always mix in the sink in case they acquire a leak


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## MzMolly65

I did a bunch of research and come up with this .. my container is #2 HDPE .  I don't understand the bit about the 1% and 50% below.  If I mix my solution 1:1, water:lye is that a 50% solution?
*
2 – HDPE – High density Polyethylene*

  Also  readily recyclable – Mostly used for packaging detergents, bleach, milk   containers, hair care products and motor oil. Is recycled into more  bottles or  bags.

Sodium hydroxide 1% - LDPE at 20C°-50C° shows little or no damage after 30 days of constant  exposure. HDPE at 20C°-50C° shows some effect after 7 days.

Sodium hydroxide 50% - LDPE / HDPE at 20C°-50C° show little or no damage after 30 days of constant exposure.

The lid on my container has no numbers on it at all so I suspect it's not safe.  It's a new container, big and with a grippy indent for picking it up BUT it's not good for pouring.  It's got a very large mouth and I thought I could put a stainless steel ladle in to scoop but my head is starting to think that's playing with fire, LITERALLY!!

I'd like to find a good container that I can store and pour safely.  I'm hesitant because I've put diluted bleach in an old dish soap bottle in the past and while the bottle was fine the pour spout ended up cracking.  That was a mess, but not near the dangerous situation I'd have on my hands if it was lye.

ETA:  how long can you store a lye masterbatch??  I'm looking at a 3 ltr stainless steel fusti with ss spigot but don't know how fast I'd use 3 ltrs of lye mix.  Can it sit indefinitely or does it go "bad"?


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## Lindy

Carolyn I use a large paint stirrer (by hand naturally) and I keep stirring until it is dissolved plus I do also add my silk at this point and that is the one that is a pain to get dissolved but I keep coming back to it until it is dissolved.  It can take me up to a hour to get it dissolved.  I too mix mine in the sink in case of a leak.


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## Tais

*Masterbatching Lye - temperature of lye*

Hi everyone
I want to start masterbatching soon, but I read that you can’t reheat lye. I mix my oils and lye when both are around 40C. So I am a bit confused on how to use the lye in this case. How do you guys use the master batch lye?


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## penelopejane

Tais said:


> Hi everyone
> I want to start masterbatching soon, but I read that you can’t reheat lye. I mix my oils and lye when both are around 40C. So I am a bit confused on how to use the lye in this case. How do you guys use the master batch lye?



You can reheat lye.  You can also use it cool and it will reheat itself and the oils as it saponifies.


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## SoapTrey

Tais said:


> Hi everyone
> I want to start masterbatching soon, but I read that you can’t reheat lye. I mix my oils and lye when both are around 40C. So I am a bit confused on how to use the lye in this case. How do you guys use the master batch lye?



When you masterbatch, you will create a concentration, for example of say 50%. Your lye solution will be 50% lye and 50% distilled water.  When you make your soap and utilize the 50% lye solution, you will need to add water to create the desired 'lye solution strength' depending on your recipe.  

Many soap makers will add the additional water to their oils first instead of mixing with the concentrated lye solution. But, if you want... you can add the additional water to your concentrated lye solution and it will heat up just as if you made a one off water/lye batch.  If you add the additional water to your oils first and then add the 'cold' concentrated lye solution to the oils, it will still heat up but tends to take a bit more time which some desire.

I hope this makes sense... I'm not quite awake yet, and gonna go grab some coffee and re-read what I just wrote!   Welcome to the forum... I just realized how old this thread is... it may be best to start a new thread asking your question.


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## DeeAnna

For the highest level of safety, if you must heat anything, then heat your oils, not the lye solution.

But Trey is right -- when you add water to a 50% NaOH solution, it will heat up quite nicely without help. Try it and see for yourself. This release of heat happens whether you add the water directly to the lye solution or add it to the oils before you add the lye. The overall mixture will not get as warm as when you add the water to just the lye, but the amount of energy released is essentially the same.

If you are trying to match the temps of your fats and your lye to start soaping, this is not really necessary -- the idea of matching temperatures is a myth. Just try to keep the temps within a reasonable range and you will be fine. You're desired soaping temp of 40 C (104 F) is not unusually warm, so in my opinion, you don't really need to worry about heating the lye.

I use room temperature NaOH solution at 50%, fats heated until the solid fats are melted and clear (about 110 F or 45 C), and room temperature water (or other water-based liquid). When all that is mixed together, my soap batter usually ends up between 95 F to 110 F (35 to 45 C).


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## Tais

Thanks everyone for your replies! It definitely helped me with my question and add even more to what I knew before!!

This was my first post here and was awesome to wake up and see your answers to my question!! 

Hope I can add to this forum too!!

A lovely week to you all!! 

It totally makes sense!!

I was just waking up when I read your reply to my question and I could get it perfectly 



SoapTrey said:


> When you masterbatch, you will create a concentration, for example of say 50%. Your lye solution will be 50% lye and 50% distilled water.  When you make your soap and utilize the 50% lye solution, you will need to add water to create the desired 'lye solution strength' depending on your recipe.
> 
> Many soap makers will add the additional water to their oils first instead of mixing with the concentrated lye solution. But, if you want... you can add the additional water to your concentrated lye solution and it will heat up just as if you made a one off water/lye batch.  If you add the additional water to your oils first and then add the 'cold' concentrated lye solution to the oils, it will still heat up but tends to take a bit more time which some desire.
> 
> I hope this makes sense... I'm not quite awake yet, and gonna go grab some coffee and re-read what I just wrote!   Welcome to the forum... I just realized how old this thread is... it may be best to start a new thread asking your question.



Thanks for the additional info about the temperatures!!!



DeeAnna said:


> For the highest level of safety, if you must heat anything, then heat your oils, not the lye solution.
> 
> But Trey is right -- when you add water to a 50% NaOH solution, it will heat up quite nicely without help. Try it and see for yourself. This release of heat happens whether you add the water directly to the lye solution or add it to the oils before you add the lye. The overall mixture will not get as warm as when you add the water to just the lye, but the amount of energy released is essentially the same.
> 
> If you are trying to match the temps of your fats and your lye to start soaping, this is not really necessary -- the idea of matching temperatures is a myth. Just try to keep the temps within a reasonable range and you will be fine. You're desired soaping temp of 40 C (104 F) is not unusually warm, so in my opinion, you don't really need to worry about heating the lye.
> 
> I use room temperature NaOH solution at 50%, fats heated until the solid fats are melted and clear (about 110 F or 45 C), and room temperature water (or other water-based liquid). When all that is mixed together, my soap batter usually ends up between 95 F to 110 F (35 to 45 C).



Sorry, was just new here  They made a new thread for me  




MzMolly65 said:


> bumping an old thread rather than starting a new one.
> 
> I want to masterbatch some lye water too and I have a # 2 container with a screw on lid, will that be adequate to store a 50/50 solution?


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## donnebonn

Sanguine said:


> Hii,
> I was wondering if you can store lye water in the fridge. Or any other type, with milk, wine, beer,...
> In hp or cp i wouldnt be bothered storing it, but when making whipped soap, chilled lye is wanted.
> It takes a few hours to chill lye water, what if for whatever reason you cant make the soap that day or the following days... Can you store lye water?
> 
> Thanks in advance!
> 
> Edit: sorry, just noticed that i'm in the wrong part of the forum..


Could you store it in a glass mason jar? And would it need to be refrigerated, or can I leave it on a shelf in the house...labeled, of course!


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## artemis

donnebonn said:


> Could you store it in a glass mason jar? And would it need to be refrigerated, or can I leave it on a shelf in the house...labeled, of course!



Over time, the lye will etch the glass, causing it to weaken. This is a potentially dangerous situation. For this reason,  glass  is not recommended for soap-making.


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## Sally Buffam

donnebonn said:


> Could you store it in a glass mason jar? And would it need to be refrigerated, or can I leave it on a shelf in the house...labeled, of course!


Hi, you can store your NaOH solution (lye) in borosilicate  (pyrex) laboratory glassware. Keep in a safe area and label. I prepare a g/ml solution and keep at ambient temperature, I dilute when necessary. works well.


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## DeeAnna

Sally Buffam said:


> Hi, you can store your NaOH solution (lye) in borosilicate  (pyrex) laboratory glassware....



I gather you have the training to know precisely what you're doing AND you have access to exactly the proper glassware. In that case, by all means do what you feel is best for your personal situation. But you've decided to provide this advice to a broad audience, and I want to take issue with that choice.

This is your first post and you may not realize this, but we've had a lot of discussions over the years about using glassware to store NaOH. I have learned from these discussions that a lot of people on this forum do not know there is a big difference between the high quality Pyrex glassware sold by reputable chem lab suppliers versus the household "pyrex" glassware sold in Walmart. To further confuse the issue, I also know there is a lot of cheap knockoff "lab" glassware being sold on Amazon and the like. There is no way for most everyday non-chemistry-geek people to tell the difference between a knockoff versus the real thing.

So ... I ask that you do not advocate the idea of storing NaOH solution in _any _type of glass on this forum. Just don't. Please err on the side of giving conservative advice suitable for everyone with a wide variety of skill and education levels who only have access to everyday supplies and equipment from places like Walmart and Amazon.

Furthermore, even borosilicate glass breaks a lot easier than plastic or metal, so any glass container is less safe for storing NaOH compared with other materials. This is especially true in an environment, such as the home, that is less controlled and regulated than a chem lab.


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## Sally Buffam

DeeAnna said:


> I gather you have the training to know precisely what you're doing AND you have access to exactly the proper glassware. In that case, by all means do what you feel is best for your personal situation. But you've decided to provide this advice to a broad audience, and I want to take issue with that choice.
> 
> This is your first post and you may not realize this, but we've had a lot of discussions over the years about using glassware to store NaOH. I have learned from these discussions that a lot of people on this forum do not know there is a big difference between the high quality Pyrex glassware sold by reputable chem lab suppliers versus the household "pyrex" glassware sold in Walmart. To further confuse the issue, I also know there is a lot of cheap knockoff "lab" glassware being sold on Amazon and the like. There is no way for most everyday non-chemistry-geek people to tell the difference between a knockoff versus the real thing.
> 
> So ... I ask that you do not advocate the idea of storing NaOH solution in _any _type of glass on this forum. Just don't. Please err on the side of giving conservative advice suitable for everyone with a wide variety of skill and education levels who only have access to everyday supplies and equipment from places like Walmart and Amazon.
> 
> Furthermore, even borosilicate glass breaks a lot easier than plastic or metal, so any glass container is less safe for storing NaOH compared with other materials. This is especially true in an environment, such as the home, that is less controlled and regulated than a chem lab.


Your right - I work in a laboratory, my assumption was that anyone using sodium hydroxide would have knowledge such as safey issues, did not realize. I wanted to share as the information I have receive from this forumn has  been very beneficial to my quest in soap making and I wanted to give back.. I understand your rational. Sorry!


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## DeeAnna

Thank you for your understanding, kind words. I'm a chemical engineer and have worked as a chem lab technician, so I appreciate your point of view. I also have to shift mental gears when in the handcrafted soap making world -- soap makers come in all colors, flavors, shapes and sizes!


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## penelopejane

Really easy to save your old liquid laundry detergent bottles with a 5 in the triangle on the bottom and reuse them for liquid (masterbatched) or dry NaOH.  They have a great secure lid and mine have a pouring spout and handle so are great.  I take off the labels and write on them with black texta exactly what they are.  I also do not store them above head height.


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## Relle

donnebonn said:


> Could you store it in a glass mason jar? And would it need to be refrigerated, or can I leave it on a shelf in the house...labeled, of course!



Sanguine hasn't been here in 4yrs, so probably won't see your quoted post to them. This thread is from 2012, ( 7 yrs old) so please post another thread and link to this one if necessary.


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## earlene

Even thought this thread is very old, since it has been brought back up and includes unsafe practice ideas, I felt it necessary to comment on one of those ideas that is very dangerous.

I strongly advise against storing any caustic liquid in a food refrigerator EVER.  Even well labelled lye solution at the strenths used for soap making should NEVER be in the same refrigerator as one's food supply.  Of course storing lye solution in a refrigerator is not necessary at all anyway, but it should really NEVER be stored with drinks or food.

Granted, most of us know better, but think of the kids or others in your household and the potential for disaster.


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## cmzaha

I totally agree with Earlene. I saw that post about storing in the fridge. One example would be, I store my hummingbird nectar in the fridge in a labeled plastic container. While it is not something dangerous it shows how severe accidents can happen. I also store empty Gatorade bottles of water to get could so I can add in my water flavoring. More than once I have picked up the container then remember it is sugar water. It could just as well be lye if I had it stored in the fridge.

And there is a big difference in the quality of Lab quality beaker and Amazon cheap beakers, even with both being labeled as borosilicate I have both and more than once the cheap Amazon beakers have had the bottoms fall out from heat. I have never had it happen with the ones purchased from a Lab supplier, those I have only broken when I have dropped them on the floor or tile counter. I will mention I never mix my lye solution in either quality beaker.


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