Citrates : The Chemistry behind..

[Lankan]

I've read about ions of sodium & potassium Citrates improving the soap by reducing the soap scum by binding up the metal ions, thus act as a clelating agent.

https://classicbells.com/soap/citrate.html

the above article by DeeAnna provides simplified approach to use of Cirtates in the soaps. whilst adding Citrate directly to the soap is an approach, combining Citric acid with either Baking Soda( Sodium Bicarbonate), NaOH or KOH will also produce the Citrates. However I was not able to find exactly the ratio of ingredients to add in this regard. Hence I tried to build a excel to figure out what exactly should go into have a certain amount of output as Citrate.

Attached herewith is the excel file (in zipped folder as uploading excel file is not allowed) containing the balanced chemical formulas of combining the citric acid with any of the three alkalies and extended it further to calculate the cost of producing 1 unit of Citrate from the ingredients (assumed prices used).

It also allows you to change the desired concentration of Citrate in your soap and gives you the amount of Citric acid and the additional alkali required over and above the Alkali/Lye used in the saponification process.

I've locked all the cells except for those which are highlighted in yellow (input cells) to avoid accidental changes and deletions. However if you want to recheck the formulas you can do so by un-protecting the file.

 

[KimT2au]

thank you for that, @Lankan. Well, I have learned something today ... I did not know you could attach an excel file in the form of a zipped file.

 

[DeeAnna]

...I was not able to find exactly the ratio of ingredients to add in this regard....

If you look at my article on citric acid, you'll see "...10 g citric acid neutralizes 6.24 g NaOH. 10 g citric acid neutralizes 8.42 g KOH...." And if you look at the end of my article on citrate, you'll see a link to Galaxy's thread about making citrate from baking soda and citric acid. In the first post, Galaxy states "...1 gram of citric acid (CA) is neutralized with 1.3124 grams of baking soda (BS)...."

The numbers in your calculations check out close to ours.

Some advice you didn't ask for, but I'm going to offer it anyway -- If you would like more people to benefit from using your spreadsheet, I'd simplify it a fair bit. Your spreadsheet as written is too detailed to encourage its use by most people most of the time. Most soapers just want to know the answers; they're usually not too interested in (or scared off by) the math and chemistry involved between the input and the output.

What about a simpler form where one enters the desired units of measure, the total weight of oils, the desired dosage of citrate in percent, and the alkali to be used? The output should be simple too -- just the weights of citric acid and alkali.

 

[Lankan]

thank you for that, @Lankan. Well, I have learned something today ... I did not know you could attach an excel file in the form of a zipped file.

Ha ha great..

If you would like more people to benefit from using your spreadsheet, I'd simplify it a fair bit. Your spreadsheet as written is too detailed to encourage its use by most people most of the time. Most soapers just want to know the answers; they're usually not too interested in (or scared off by) the math and chemistry involved between the input and the output.

What about a simpler form where one enters the desired units of measure, the total weight of oils, the desired dosage of citrate in percent, and the alkali to be used? The output should be simple too -- just the weights of citric acid and alkali.

Thanks, I actually started to work on this excel to understand the ratios you've mentioned in your article. I also noted that the Citric acid : Baking soda ratio tallying with what's stated in your article. I'll try to simplify as you suggested and insert a home page summarizing the inputs and outputs keeping the science and math in a separate sheet.

 

[Lankan]

What about a simpler form where one enters the desired units of measure, the total weight of oils, the desired dosage of citrate in percent, and the alkali to be used? The output should be simple too -- just the weights of citric acid and alkali.

As suggested by DeeAnna; I added a summary page to the excel file I shared earlier. Hope it would be useful to the community.

Unfortunately I'm not familiar with the imperial measurement system used in US. hence just mentioned as units. please note the ingredients units will be the same measure of weight used in the weight of the oil (grams, Ounce etc).

 

[DeeAnna]

All you need is a single conversion -- just show ounces (wt) and grams and that will satisfy the vast majority of people around the world.
0.035274 ounce = 1 gram
23.35 grams = 1 ounce

 

[Lankan]

As suggested by DeeAnna I've added Ounce & Grams as input and output units. All the cells highlighted in yellow can be changed.

Google says the the conversion ratio between ounce & grams is 28.34952, which I have used in the conversion.

 

[DeeAnna]

Well done!

23.35 vs 28.34952 ... oops, my error. I typed a 3 rather than an 8. Thanks for catching that.

 

[camproses]

When should these ingredients be added , and how? Thank you!

 

[DeeAnna]

@camproses -- here are my suggestions: https://classicbells.com/soap/citrate.html

 

[Lankan]

Well done!

Thanks, I'm excited.