Questions regarding Lye

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

shunt2011

Moderator Emeritus
Supporting Member
Joined
Apr 2, 2012
Messages
15,450
Reaction score
9,842
Location
Michigan
If stored properly kept in a cool dry place it may be fine. What’s there any clumps in it? It can absorb moisture. But it should still dissolve I would think. You could strain it. It may make a softer soap.
 
How long did you wait and did you stir? It takes a while to dissolve.
 
Yes, lye can go bad. Try straining it, if it dosen't all dissolve. You could try mixing up a smaller batch of lye/water for a one pound batch before using a lot of oil that could be wasted.
 
In addition to the above questions/comments:

How much lye exactly and how much water exactly? (Example: 100g NaOH; 100g distilled water)
Sodium hydroxide (NaOH) dissolves in an equal weight of water, but if not enough water, it will not completely dissolve.

Did you add the lye slowly to the water and stir while adding? Did you continue stirring?
I have found lye dissolves easier if poured slowly into the water, while stirring between each addition of lye crystals. When that is dissolved, then adding more lye, etc.

Was the water at room temperature or was it cooler? (Example ice cubes)
The one time I have seen NaOH not dissolve completely (or precipitate back out after dissolving) was when I dumped it all in at once on top of frozen milk, didn't stir enough and kept the container in an ice bath. I don't prepare lye solution that way anymore, btw. I learned my lesson.

I just made soap again after a couple of years and the lye did not dissolve in the water completely, I was afraid to use it, does lye get old after so many years? Please help.

Yes, it gets 'old'. If not kept air-tight and without a large gap at the top of the bottle (where there is air in the bottle) in a location without any humidity, the lye can absorb moisture from the air, reducing it's purity. A lye calculator assumes 100% purity, but it could be much lower, say 85% pure, in which case the resulting soap has a much higher superfat than calculated. But that should not make it unable to dissolve. In fact, I would expect quite the opposite. I would expect it to dissolve easier due to having more water than needed if you use a lye calculator's defaults.
 
Is it caked to the bottom, or is it floating around in grains not dissolving? If it is caked to the bottom, put on gloves and eye protection. Pour the lye water into a safe container. Use a butter knife to gentle chisel out the lye cake on the bottom of your container. Break the cake into small bits. Put the bits of lye into the water and stir gently until they dissolve.
 
Lye can become "clumpy" if it absorbs moisture from humid air.

Store you "loose" lye in a 5 or 7 gallon pail, but replace the snap on lid with a Gamma Seal lid, which has two parts: The rim snaps onto your pail and then the center cap screws into the rim and locks out moisture with a gasket. Gamma Seal lids are sold at Home Depot,
leaktite-paint-buckets-lids-5gamma6-64_145.jpg

(They call them "Leak Tite" but look at the big picture and the embossed plastic says Gamma Seal.)

https://www.homedepot.com/p/Leaktite-5-gal-Screw-Top-Lid-5GAMMA6/203205720

Dry lye releases much heat as it dissolves into water. If you go about 2:1 water to lye, by weight, then this is a good ratio: As the solution is still nice and heavy, but there is enough water that on those "rush" sessions where you can't wait for the lye solution to cool, you can substitute ice instead of water, and the amount of heat released by this amount of lye will be insufficient to melt this TOTAL weight of ice, so you can use some ice, and some water, and control your immediate temperature.

Don't mix dry lye with hot water . . . it will boil spontaneously.
 
Lye can become "clumpy" if it absorbs moisture from humid air.

Store you "loose" lye in a 5 or 7 gallon pail, but replace the snap on lid with a Gamma Seal lid, which has two parts: The rim snaps onto your pail and then the center cap screws into the rim and locks out moisture with a gasket. Gamma Seal lids are sold at Home Depot,
leaktite-paint-buckets-lids-5gamma6-64_145.jpg

(They call them "Leak Tite" but look at the big picture and the embossed plastic says Gamma Seal.)

https://www.homedepot.com/p/Leaktite-5-gal-Screw-Top-Lid-5GAMMA6/203205720

Dry lye releases much heat as it dissolves into water. If you go about 2:1 water to lye, by weight, then this is a good ratio: As the solution is still nice and heavy, but there is enough water that on those "rush" sessions where you can't wait for the lye solution to cool, you can substitute ice instead of water, and the amount of heat released by this amount of lye will be insufficient to melt this TOTAL weight of ice, so you can use some ice, and some water, and control your immediate temperature.

Don't mix dry lye with hot water . . . it will boil spontaneously.

I store my lye bottles in a 5 gallon bucket with a Gamma Seal lid AND desiccant in the bucket as well. I consider this a better way than loose lye. Plus I can keep NaOH and KOH bottles in the same bucket. I also keep lye bottles that have been opened inside a zip lock back in addition to being inside said bucket. May be overkill, but I am happy with the results.
 

Latest posts

Back
Top