Caustic Soda

[JessCharli]

Am I able to use caustic soda 98%?! It says it’s “perfect” for soap making. (Newbie)

 

[Kittish]

As long as it's sodium hydroxide, then yes. I'm not aware of anything else commonly called caustic soda.

 

[JessCharli]

Yeah it says it is, thanks!

 

[earlene]

What is the other 2% would be my question.

ETA: If you are able to buy pure 100% caustic soda (sodium hydroxide) that would be preferable to 98% pure.

 

[DeeAnna]

You cannot buy NaOH that is 100% pure. It just doesn't happen. The analyses I've looked at for commercial NaOH runs anywhere from 92% to 98%, with most running in the middle 90s. The NaOH I use is about 95-96% pure.

The OP's NaOH has a purity of 98% from the manufacturer, which means 2% is contaminants that naturally occur in NaOH. The main contaminants are water and sodium carbonate -- things that naturally accumulate in NaOH when it is exposed to the air. That's actually quite reasonable. Remember, however, that improper storage at the distributor and in your own soap kitchen can quickly reduce that purity, so store it properly!

Sometimes people confuse IMPURITIES with ADDITIVES. Additives are things intentionally added to the product. So some drain cleaners might be a mixture of NaOH and coloring and perhaps some aluminum particles. The colorant and the aluminum are deliberately added to the NaOH.

 

[JessCharli]

You cannot buy NaOH that is 100% pure. It just doesn't happen. The analyses I've looked at for commercial NaOH runs anywhere from 92% to 98%, with most running in the middle 90s. The NaOH I use is about 95-96% pure.

The OP's NaOH has a purity of 98% from the manufacturer, which means 2% is contaminants that naturally occur in NaOH. The main contaminants are water and sodium carbonate -- things that naturally accumulate in NaOH when it is exposed to the air. That's actually quite reasonable. Remember, however, that improper storage at the distributor and in your own soap kitchen can quickly reduce that purity, so store it properly!

Sometimes people confuse IMPURITIES with ADDITIVES. Additives are things intentionally added to the product. So some drain cleaners might be a mixture of NaOH and coloring and perhaps some aluminum particles. The colorant and the aluminum are deliberately added to the NaOH.

I actually googled around after posting this and did find your reply on someone else’s post, so thank you! Very helpful