Storing lye water

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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?
 
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.
 
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.
 
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).
 
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

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!!!

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 :)


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?
 
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!
 
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.
 
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.
 
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!
 
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!
 
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.
 
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.
 
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.
 
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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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 :)At what temp do you put your lid on?
 
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