containers to mix lye

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whisks

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i have been mixing my lye in a stainless steel saucepan (in the laundry where all my other soap stuff lives - too risky in the kitchen) and have seen you tube videos and other people mention that they ix their lye in plastic buckets. i am assuming it is safe to mix lye in plastic containers but have always been concerned that the lye would get too hot and melt the plastic. comments please.
 
I use a plastic pitcher that I set in the sink, once my lye is mixed I fill the sink with cold water & ice to cool it to the desired temp to soap with.
 
I use an empty plastic 2 litre ice cream container and no trouble with melting etc. At least it has a lid so if I run out of time and don't get the soap made I just put on the lid and its ready when I get back to it.
 
whisks said:
i am assuming it is safe to mix lye in plastic containers but have always been concerned that the lye would get too hot and melt the plastic. comments please.

Plastic is fine, but there are certain plastics to stay away from because they are not compatable with lye.

Here is what I have in my notes regarding which are safe plastics to use with lye, and which are not:

"Best one is polypropylene (#5), since it's resistant to alkali and can withstand boiling water, plus it goes into dishwasher without problems (this is the whitish-transluscent plastic that some of the Rubbermaid containers are made from). Next best one is HDPE (#2), though it can only be used at 190 F. After that, you have LDPE (#4) (150F) and PVC (#3) (140F).

Do not put lye into the following plastics because they are not alkali resistant: polycarbonate (the crystal clear Rubbermaid containers); nylon (polyamide); polystyrene plastics (PS #6, or ABS which is a type of styrene plastic [acrylonitrile butadiene styrene); and PETE (#1). The numbers in parenthesis are the recycling codes found on plastic items.

Acrylics are ok for very short term exposure, but not for repeated use or long term storage. "


I used PETE #1 once and lived to regret it (this was before I knew which plastics to avoid with lye). The lye solution ate a hole right through the plastic.


Edtited to add that stainless steel is a great choice to mix and store lye in.

IrishLass :)
 
thank you for that IrishLass. i might just continue using my saucepan, then. while the lid isn't airtight, i try to keep it in a hard to get at spot. the problem i think i'll have with the plastic lids is that if they are airtight, i may have difficulty removing them and may splash myself. i'm not infirm, yet, but i like being careful.
 
I tried to look for plastic cup that could withstand heat- as mentioned on them, but they can only reach 100C so I didn't get these
I tried to look for a glass pyrex cup (big one for measuring liquid), which would probably be the best of all- but the shops I went too didn't have that. finally I setteled for a bowl that is actually the lid of a washing mashine, it is durable and was build to withstand heat and such
 
Actually, I wanted to add that PTFE containers can not be exposed to heat temperatures as high as you can with glass. The user has to be sure they do not overheat PTFE material. If the PTFE is overheated, especially in air, it can start to break down by both thermal decomposition and oxidation, resulting in fumes of HF which should not be inhaled under any circumstances.
 
FreeRabbit said:
I tried to look for plastic cup that could withstand heat- as mentioned on them, but they can only reach 100C so I didn't get these
I tried to look for a glass pyrex cup (big one for measuring liquid), which would probably be the best of all- but the shops I went too didn't have that. finally I setteled for a bowl that is actually the lid of a washing mashine, it is durable and was build to withstand heat and such
BluebirdMama said:
Actually, I wanted to add that PTFE containers can not be exposed to heat temperatures as high as you can with glass. The user has to be sure they do not overheat PTFE material. If the PTFE is overheated, especially in air, it can start to break down by both thermal decomposition and oxidation, resulting in fumes of HF which should not be inhaled under any circumstances.
Absolutely do NOT use glass. Cuz shattered glass and lye solution all over is hugely dangerous, making those fumes seem like mother's milk in comparison. Even Pyrex can shatter, especially after being etched by repeated exposure to lye and then experiencing the sudden temp change that occurs when lye meets water.

I don't care if you've never had a problem. I don't care if you use canning jars. I don't care if you have saint bob's blessing. Do NOT mix your lye solution in ANY kind of glass.
 
I use a big white bucket I got at Home Depot. it is HDPE and it was less then $10.

I have made several batches of cp soap in it and never had a problem.
 
I have an old Tupperware Classic sheer pitcher I like it because it has the lid that seals air tight and you have to push the button to open it. I mix my lye water, let it cool then pop the lid on and put it out of reach until I'm ready to use it.

I only had one problem ... which was MY fault ... I put the lid on before it cooled and the pressure from the build up of heat caused the lid to pop off. Live and Learn ...
 
Actually, my point I was trying to explain was NOT to use that type of plastic material..


[/quote]Absolutely do NOT use glass. Cuz shattered glass and lye solution all over is hugely dangerous, making those fumes seem like mother's milk in comparison. Even Pyrex can shatter, especially after being etched by repeated exposure to lye and then experiencing the sudden temp change that occurs when lye meets water.

I don't care if you've never had a problem. I don't care if you use canning jars. I don't care if you have saint bob's blessing. Do NOT mix your lye solution in ANY kind of glass.[/quote]
 
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