Citric acid as a chelator
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A thought sprung up in my head. The theory of adding a chelating agent like SC for boosting soap efficiency is definetly there.
BUT...
Is the reaction between the hard water (Ca/Mg?) and the citrate even fast enough to be noticable while swiftly washing your hands/body?
For example if I put a bunch of citric acid in a bowl with my hard water, I wouldn't expect instant precipitation of calcium citrate, I'd expect it to take a while.
Doesn't seem all that practically useful now that I think about it. Perhaps a wee bit more if using soap as a laundry detergent where the reaction between the chelator and hard water has time to happen.
Thoughts?
BUT...
Is the reaction between the hard water (Ca/Mg?) and the citrate even fast enough to be noticable while swiftly washing your hands/body?
For example if I put a bunch of citric acid in a bowl with my hard water, I wouldn't expect instant precipitation of calcium citrate, I'd expect it to take a while.
Doesn't seem all that practically useful now that I think about it. Perhaps a wee bit more if using soap as a laundry detergent where the reaction between the chelator and hard water has time to happen.
Thoughts?
In informal tests, it took just a few seconds for soap to react with hard water to form milky soap scum. It took longer for EDTA to reverse that soap scum and turn the water clear again. See: http://www.soapmakingforum.com/showthread.php?t=52456
Reversing scum formation is not necessarily the same as preventing scum from forming, however. I can tell when I use soap without EDTA in the shower vs soap that includes it, especially when our home water softener runs out of salt so the water isn't especially soft. I don't think it's realistic to expect a chelator in soap to totally prevent scum -- it would take an unrealistically high dose to get that kind of result -- but it definitely helps.
I will also say you're going to see more obvious results from a chelator when you are showering or washing your hands -- situations where there is only a small amount of water and hard water minerals for the chelator to deal with. It would take a LOT more chelator to deal with the hard water minerals in a washing machine or kitchen sink or bath tub full of water. You're better off to add the correct amount of washing soda or other water softening agent (and/or use a whole house water softener) to control soap scum in these situations.
Reversing scum formation is not necessarily the same as preventing scum from forming, however. I can tell when I use soap without EDTA in the shower vs soap that includes it, especially when our home water softener runs out of salt so the water isn't especially soft. I don't think it's realistic to expect a chelator in soap to totally prevent scum -- it would take an unrealistically high dose to get that kind of result -- but it definitely helps.
I will also say you're going to see more obvious results from a chelator when you are showering or washing your hands -- situations where there is only a small amount of water and hard water minerals for the chelator to deal with. It would take a LOT more chelator to deal with the hard water minerals in a washing machine or kitchen sink or bath tub full of water. You're better off to add the correct amount of washing soda or other water softening agent (and/or use a whole house water softener) to control soap scum in these situations.
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I am also going to use citric acid as a chelator with NaOH. But at what point do I add it? After I have added NaOH to the water and it has all dissolved? Or after a certain temperature? Or before/with the lye? Or did I just confuse this dramatically?
Hello @LoveSonam. This post is 4 years old but seeing as how I have an answer that can help which doesn't happen often I'm just going to go ahead! DeeAnna has written this very useful information: Citric acid, Citrus juice | Soapy Stuff and if you are not confident with the maths then you can just use Soapmakers Friend as your soap calculator and it does it for you. Add your citric acid to your water and dissolve before adding the lye
Perfect! Thank you so much!!Hello @LoveSonam. This post is 4 years old but seeing as how I have an answer that can help which doesn't happen often I'm just going to go ahead! DeeAnna has written this very useful information: Citric acid, Citrus juice | Soapy Stuff and if you are not confident with the maths then you can just use Soapmakers Friend as your soap calculator and it does it for you. Add your citric acid to your water and dissolve before adding the lye
I measure out my distilled water then add the citric acid. Stir until all the citric acid is dissolved. Then start adding the lye.
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