Tetrasodium EDTA woes... Please help!

[Squirrelly]

Hi soapy friends! I'm completely bamboozled here & am hoping someone can help! I'm not new to soapmaking, but I AM new to adding Tetrasodium EDTA to my recipes. Admittedly, I lurked on this website for helpful info & found a TON!! There's one member in particular who wrote & linked a VERY informative article, which includes how to create a 50% Tetrasodium EDTA solution with distilled water (I'm SO SORRY this person's name eludes me at the moment, so unfortunately, I'm unable to give proper credit where it's very much due).

I went ahead & ordered the Tetrasodium EDTA from a large, well-known online supplier. When I went to make the solution, I was mindful to follow instruction, as well as proper weights/measurements needed to make the solution in distilled water. Three days later though (and HOURS UPON HOURS of stirring), the Tetrasodium EDTA wouldn't dissolve AT ALL.

I emailed the company I purchased from & explained the problem. The customer service I received was great. I was told the Tetrasodium EDTA they personally had on-hand, and tested on my behalf, dissolved easily in water, and that it was likely I accidentally received the wrong item due to new employees being trained in their warehouse. The rep I spoke with told me she'd send the CORRECT Tetrasodium EDTA right away, and she did just that! PROBLEM SOLVED... Or so I thought!

So here I am this morning, making my 50% Tetrasodium EDTA/distilled water solution (take: two), and at this point, I JUST DON'T GET IT!!! It's nothing but the same problem all over again!! Once again, I followed instruction & weights to a "T", and once again, the Tetrasodium EDTA just separates from the distilled water & settles to the bottom like fine, gritty, white, beach sand; completely insoluble in distilled water... I'd like to rip my hair out now lol!

So, I'm way too embarrassed to email the supplier AGAIN with the same exact problem, but I'm thinking it has to be one of 3 things: Either the water company is lying about their distilled water being distilled, which I doubt entirely; the supplier I purchased from never "tested the product" like they said they did & there's a major problem with the product itself; or I'm terrible at reading comprehension & am doing something totally wrong here. Either way, I need help so badly!!!!

If anyone could offer help as to what could possibly be going wrong, I would be SO grateful, I'll give you my first born (he's a pre-teen, so he's becoming quite big for his britches anyway HAHAHA!)!!! In all seriousness though, THANK YOU SO MUCH for reading my long post and sharing any info you might have!❤

 

[DeeAnna]

DIsodium EDTA is not very soluble in water. I imagine that's what you're getting, regardless of what name they put on the label. TETRAsodium EDTA dissolves in room temperature water in a few minutes with very little effort.

I honestly don't think you got tetrasodium EDTA in either shipment. They need to take some of the powder and try to dissolve it in plain distilled water. If it dissolves, it's TETRA; if it doesn't, it's DI.

The way to convert DI to TETRA and get it to dissolve is to mix the DI into a weak sodium hydroxide (lye) solution, not plain water.

It would seem like you should be able to dump the DI into the lye solution you normally mix up when making soap, but that won't work. TETRA is soluble in weak alkaline solutions, but TETRA is insoluble in the strong lye solutions that we have to use to make soap.

***

Disclaimer: I have not done the following personally nor have I dug into the math to confirm the numbers. Try this at your own risk.

If I had DIsodium EDTA and wanted to convert it to TETRA, I would probably try something like this. It should make an approximately 50% mixture of TETRAsodium EDTA and water with a small excess of NaOH --

Distilled water 100 g
NaOH 22 g
Mix together to make a lye solution. Let cool until the solution is no more than pleasantly warm.

Disodium EDTA 100 g
Stir into the lye solution until fully dissolved. Store in a leakproof container at room temperature.

Background information I used to come up with the weights -- How to formulate tetrasodium EDTA and etidronate — Cosmetic Science Talk

 

[Squirrelly]

@DeeAnna, I could seriously hug you right now if hugs weren't currently illegal!!! YOU NAILED THIS STRAIGHT ON THE HEAD!!!! I followed your instructions above to the letter, and guess what? IT' DISSOLVED, AND IS BEAUTIFULLY CLEAR!!! THANK YOU, THANK YOU, THANK YOU!!! You are absolutely WONDERFUL to have gone out of your way to get this info for me!!!

So the mystery is solved... I kept getting sent Disodium EDTA under a Tetrasodium EDTA product listing. Not to bad mouth the company by any means (they were very prompt & kind to answer my emails & resend the product- even tho it was the wrong one), but just to give other crafters a heads-up (and hopefully spare others the frustration), I did purchase this at makeyourown (aka: saveoncitric).

Now my next question is a moral one though! Do you think as a fellow crafter, the right thing to do here would be to email the company and tell them of their mix-up? I'd hate for anyone else to receive the wrong product, but I wouldn't want the company to think I'm coming at them with a "you messed up!" mentality. What do you think? Share the info & experience of the situation so they can correct their listing, or leave it be?

In any case, you are absolutely FANTASTIC Deeanna and I cannot say THANK YOU enough for your help!! You've saved the day (LITERALLY! I'm so behind in my soap making), and I owe ya a pre-teen! THANK YOU AGAIN SO MUCH!!!!!

@DeeAnna - ALSO! We're you the amazing crafter who published the article about Tetra EDTA & how to make a 50% solution?! That article was so helpful, I took notes!!

 

[DeeAnna]

Yeah, it's an article I wrote. It's in the "Soapy Stuff" section of my website -- Soapy Stuff: Soapy Stuff

I'm going to update the article with the info from this thread -- I know you're not the only one who would like to convert di to tetra.

 

[atiz]

@Squirrelly, I would probably tell them, who knows how much mislabeled Disodium EDTA they are unaware of... I think there is a way to just tell them nicely, not really as a complaint but as an FYI.
Glad DeeAnna's method worked!

 

[CaraBou]

That's a pretty cool success story. Way to go DeeAnna! And Squirrelly, good on you for asking the question. Hope to see you around more.

 

[Sunny1981]

Yeah, it's an article I wrote. It's in the "Soapy Stuff" section of my website -- Soapy Stuff: Soapy Stuff

I'm going to update the article with the info from this thread -- I know you're not the only one who would like to convert di to tetra.

Thank you so much for all the information you provided..I started using citric acid as a chelator but now I have disodium EDTA and planning to convert to trisodium EDTA and use it. I remember reading somewhere that we can use both citric acid and EDTA ..so wondering if I can use both in one recipe..or what are your thoughts? Thanks again!

 

[DeeAnna]

It's actually citrate that's the chelator. Citrate what you get when citric acid reacts with sodium hydroxide or potassium hydroxide. I totally understand why a person might say citric acid when they mean citrate -- I do it sometimes too. Unfortunately using "citric acid" rather than "citrate" can mislead people who are new to the idea of using a chelator in soap.

Back to your question -- There have been people who have had problems with their soap doing strange things when they load it up with several types of salts. I haven't heard anyone using a citrate-EDTA combo, so I can't speak about that. What I can say is to tread carefully with this idea of using multiple salts/chelators in soap. If one is effective, two is not necessarily better.