Sodium gluconate

[nframe]

Is it possible to add this to soap (instead of EDTA)? This is what I read about it:
The outstanding property of sodium gluconate is its excellent chelating power, especially in alkaline and concentrated alkaline solutions. It forms stable chelates with calcium, iron, copper, aluminium and other heavy metals, and in this respect, it surpasses all other chelating agents, such as EDTA, NTA and related compounds.

 

[DeeAnna]

Looks like it might work. Give it a try and let us know!

 

[nframe]

Looks like it might work. Give it a try and let us know!

What percentage should I try? 0.5% of oil weight?

 

[DeeAnna]

I was seeing amounts from 0.1% to 1%. So 0.5% sounds like a reasonable number. But other than a 5 minute skim session, I have utterly no knowledge of this chemical, so take my comment for what it's worth.

 

[nframe]

Thanks DeeAnna. I have ordered the stuff. I'll try it at 0.5% and report in due course.

 

[SaltedFig]

I like it's biodegradeability and low/non toxicity.

A quick look suggests that it might have a softening effect on the soap (it is used as a plasticiser for concrete).

Also interested in how you go

 

[penelopejane]

If sodium gluconate is a chelating agent would it also be a substitute for Citric Acid?
EDTA also hardens a soap so would sodium gluconate be a substitute for salt?

 

[nframe]

Well, I made the soap and it worked fine. The addition of the sodium gluconate did not cause anything to happen, it behaved just as it does with EDTA. What was different though is that I put the soap in the oven to do CPOP (as I usually do) but then I forgot the soap in the oven. In the evening, my husband (who was making dinner that night) switched the oven on to 180C and, after about 30 minutes, when he opened the door he saw the soap. I am amazed that it survived! (I attach a photo). The soap is really hard now but whether it is due to the baking or not, I don't know. So, all in all, it is not really a reliable experiment. I'll have to make another batch. Oh well...

 

[penelopejane]

Nice looking soap. The only time that happened to me (accidentally turning on the oven) my soap smelt like moldy socks. It never recovered. Glad you saved yours.

 

[cmzaha]

Well, I made the soap and it worked fine. The addition of the sodium gluconate did not cause anything to happen, it behaved just as it does with EDTA. What was different though is that I put the soap in the oven to do CPOP (as I usually do) but then I forgot the soap in the oven. In the evening, my husband (who was making dinner that night) switched the oven on to 180C and, after about 30 minutes, when he opened the door he saw the soap. I am amazed that it survived! (I attach a photo). The soap is really hard now but whether it is due to the baking or not, I don't know. So, all in all, it is not really a reliable experiment. I'll have to make another batch. Oh well...View attachment 29635

They turned out gorgeous and I see a Dolphin in the top right soap

 

[penelopejane]

Well, I made the soap and it worked fine. The addition of the sodium gluconate did not cause anything to happen, it behaved just as it does with EDTA.

Do you have to neutralise sodium gluconate with extra NaOH?

 

[nframe]

No, I used at 0.5% of the oil weight.

 

[penelopejane]

I have made my testers of 0.5% and 1% sodium gluconate and CA.

I know CA stops soap scum because when I first started I used to get glug in my floor drain and since using CA I don't.

I know SG is supposed to stop soap scum but how am I going to tell that it works best at 0.5% or 1% when it will take weeks of use to see if I get glug in my floor drain?

Is there a better test?

 

[nframe]

Well, I made another batch and did not cook it this time! The sodium gluconate seems to work as well as EDTA. I can't say which one is better. I suppose I'll buy whichever one is the cheapest in future.

 

[SaltedFig]

Bubble tests ...

You can test your soaps by taking a same sized piece of each soap recipe, and shaking in individual bottles of hard water.

Compare the bubbles to each other, and to a "control" soap piece (no additives) shaken in soft water.

 

[nframe]

Bubble tests ...

You can test your soaps by taking a same sized piece of each soap recipe, and shaking in individual bottles of hard water.

Compare the bubbles to each other, and to a "control" soap piece (no additives) shaken in soft water.

What a good idea! Thank you.

 

[penelopejane]

Well, I made another batch and did not cook it this time! The sodium gluconate seems to work as well as EDTA. I can't say which one is better. I suppose I'll buy whichever one is the cheapest in future.

So the soap is hard like EDTA soap?
What are the other characteristics?
I am trying to work out what I’m looking for.
My soap is probably too young to test but will try salted figs suggestions today.

 

[nframe]

So the soap is hard like EDTA soap?
What are the other characteristics?
I am trying to work out what I’m looking for.
My soap is probably too young to test but will try salted figs suggestions today.

Yes, the soap looks and feels exactly the same as with EDTA. I cannot find any special characteristics.

 

[selma]

Hi everyone!
I've been planning for ages to try sodium gluconate in soap, and still haven't done it. So now I just have to! I have hard water, and I always use citric acid in my soaps as a chelating agent. In my research I've found this PDF file on sodium gluconate which might be interesting to read. Good information! Such a shame that it's so expensive here in Bosnia and Herzegovina!

 

[penelopejane]

Not all suppliers make SG by naturally fermenting glucose.
Jungbunzlauer is the only one I’ve found so far!
There are sure to be others.