Will my soap be safe? Sodium hydroxide and S. carbonate

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Soapeysoaps

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Hi everyone, please help! So I braved it last night and made a cold process 100% coconut oil soap, only a small batch, like 500g. Thing is after leaving it in the mold last night I was packing thing away and looked again at the ingredients on my two bottles of “caustic soda drain cleaner”. (Yes I looked up that I can use it), problem is One bottle says the ingredients are sodium hydroxide, and the other bottle says both S.H and Sodium carbonate.
I can’t remember which I used!
The bottles have been used previously so I guessed that’s why there were some lumps in the bottle, I put it down and used the other but, I’m not sure which one.
If I used the mix bottle and not the S.H only will the soap be safe to use?
Sorry about it being long winded, just wanted to explain properly.
 
Sodium carbonate, soda ash, is a product of sodium hydroxide and air. It should be a very small percentage of sodium carbonate. Check to see if it says anywhere the percentage of sodium hydroxide on the one that is both. It should be like 99%.
 
Sodium carbonate, soda ash, is a product of sodium hydroxide and air. It should be a very small percentage of sodium carbonate. Check to see if it says anywhere the percentage of sodium hydroxide on the one that is both. It should be like 99%.

Thanks for replying, it doesn’t say. It’s the bottle on the right in the picture:)
 

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It's a strange label for sure, especially since sodium carbonate is listed first (it's probably not the predominant ingredient). I've never seen it like that. However, sodium carbonate is not hazardous (edit: in soapmaking). The hazardous things you have to look for in commercial drain openers are things like aluminum and other additives.

Just because I said it weird: both sodium hydroxide and sodium carbonate are hazardous... obviously they are quite alkaline, but the soap is safe.
 
It's a strange label for sure, especially since sodium carbonate is listed first. I've never seen it like that. However, sodium carbonate is not hazardous. The hazardous things you have to look for in commercial drain openers are things like aluminum and other additives.

Ok phew, somewhat relieved. I’ve tried to google it but I just get the fact carbonate is part of the hydroxide. Thanks .
 
The problem with sodium carbonate is that it won't saponify fat if you use a normal HP or CP method.

Reading the two labels -- I'm doubtful the right hand product is the same as the left hand one. Sodium carbonate is the first ingredient listed, so sodium carbonate is at least 51% of the whole.

While it's true that a product that's sold as 100% sodium hydroxide will contain some impurities due to absorbing water vapor, reacting with carbon dioxide in the air, and trace impurities from the manufacturing process, but the INGREDIENTS list should say only sodium hydroxide.
 
The problem with sodium carbonate is that it won't saponify fat if you use a normal HP or CP method.

Reading the two labels -- I'm doubtful the right hand product is the same as the left hand one. Sodium carbonate is the first ingredient listed, so sodium carbonate is at least 51% of the whole.

While it's true that a product that's sold as 100% sodium hydroxide will contain some impurities due to absorbing water vapor, reacting with carbon dioxide in the air, and trace impurities from the manufacturing process, but the INGREDIENTS list should say only sodium hydroxide.

Thanks for the reply :) so do you think I should throw them away just Incase?
 
The soap will be fat heavy if there was a lot of sodium carbonate in your lye mixture rather than the NaOH you thought it was. If so, the soap is going to be technically safe to use on your skin, but it may be soft and greasy due to a high superfat. It's hard to say if that's the case or not -- photos and words can only do so much.
 
It seems like there are two choices. You either have “good” soap or, as DeeAnna noted, you have oil heavy soap due to having much less sodium hydroxide than you needed. Is the soap firming up? That may be your best clue. The one time I made soap with only half the required amount of sodium hydroxide, the soap was the consistency of guacamole after 24 hours. I don’t think a soap short 50% or more of the required lye would have the nice edges of your soap in the photos above.
 
If you have used the mix one that means you will have a soap with soft texture as there will be unreacted oil in your batch, but if you use the other one with only caustic soda and your lye used is within the limit based on your lye calculator, then you will have a soap with harder texture. The only way you can distinguish which is only sodium hydroxide or mixture is by individually dissolving a known quantity of the two in two separate quantity of water, the same amount of water and observe the temperature. The one with higher temperature is only sodium hydroxide.
 
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It seems like there are two choices. You either have “good” soap or, as DeeAnna noted, you have oil heavy soap due to having much less sodium hydroxide than you needed. Is the soap firming up? That may be your best clue. The one time I made soap with only half the required amount of sodium hydroxide, the soap was the consistency of guacamole after 24 hours. I don’t think a soap short 50% or more of the required lye would have the nice edges of your soap in the photos above.

Yes it hardened quite quick actually, think I saw the gel phase going through it. I didn’t cover it just left them in the mold on the side in the kitchen. They were made by 9pm and when I checked by say 10 or 11 it had a dark center and light outsides, I assumed it was the gel phase and in the morning they are good and hard,(smell nice of the lavender and lemon fragrance too ;))
 
If you have used the mix one that means you will have a soap with soft texture as there will be unreacted oil in your batch, but if you use the other one with only caustic soda and your lye used is within the limit based on your lye calculator, then you will have a soap with harder texture. The only way you can distinguish which is only sodium hydroxide or mixture is by individually dissolving a known quantity of the two in two separate quantity of water, the same amount of water and observe the temperature. The one with higher temperature is only sodium hydroxide.

Oh brilliant thanks for the tip! :)
 
Yes it hardened quite quick actually, think I saw the gel phase going through it. I didn’t cover it just left them in the mold on the side in the kitchen. They were made by 9pm and when I checked by say 10 or 11 it had a dark center and light outsides, I assumed it was the gel phase and in the morning they are good and hard,(smell nice of the lavender and lemon fragrance too ;))
I think you won the lottery :)
 

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