Attempt to make a powerful toilet bomb!

Formulating

Attempt to make a powerful toilet bomb!

Posted by steamedrice on August 18, 2021 at 9:36 am

Dear all amazing formulators,

I’ve used an array of toilet foaming cleanser products. Recently came across one from Japan. Its a foaming spray with bleach in it. Works quite well.

I thought to myself, why not make toilet bath bombs????? Most toilet bath bombs are based on the recipe of regular bath bombs and don’t really foam up much. I’m looking for one that foams all the way up to the rim in a relatively short time.

I thought about the elephant toothpaste reaction & came up with the following formula:

>Sodium Percarbonate 100g

>Anhydrous citric acid 25g

>Calcium hypochlorite 40g

>Yeast 15g

> 10 drops of Tea Tree Essential oil
Sphere mold qs. 180g

Turned out it didn’t foam as much as I anticipated!

I added yeast in hope that it’d react with the Hydrogen Peroxide in Sodium Percarbonate. It seemed to work a little but not very well.

can anyone guide me please? Am I missing someone in my formula?

Thanks all!!

steamedrice replied 3 years, 2 months ago 5 Members · 13 Replies
13 Replies

OldPerry

Member
August 18, 2021 at 2:23 pm

As far as I can tell, you have no foaming agent in there to trap the gas and make bubbles.
You also have included an oil that will reduce foam.
In the elephant toothpaste experiment they include a surfactant like soap that captures the gas as it’s formed. I’m not sure if the enzyme in the yeast will produce enough gas fast enough but without a foaming agent, all the gas it does produce just goes into the air.
Pharma

Member
August 18, 2021 at 7:26 pm

@Perry Yeast is added as catalyst to kickstart decomposition of hydrogen peroxide (H2O2 is what’s originally used in the elephants toothpaste concoction and what’s created when dissolving sodium percarbonate in water). There are other, better, catalysts available such as potassium iodide.
chemicalmatt

Member
August 18, 2021 at 7:35 pm

@steamedrice, there is one basic flaw in that formula of yours: the ratio of percarbonate to citric acid is 4:1, where it should be closer to 2:1, especially with Ca hypo in there. That alone will produce a lot more fizzy. Also, I assume you are using coated percarbonate and hypochlorite? If not you’ll experience constant sublime reduction of the oxygenators to the point where there’s not much left to produce gas on solution/acidification. I used to test formulas like this in sealed f/f/s pouches, and even the coated percarbonates will sublime. Per Perry’s comment, no yeast enzyme I know of will produce gas very fast. I’d delete it entirely - no need for it. He’s also right about the soap. Add some SLS powder to that sucker and see what happens. SLS is peroxide stable.
Pharma

Member
August 18, 2021 at 8:54 pm

@chemicalmatt Right, that bomb combines two different strategies, one is CO2 formation due to reaction of citric acid with carbonate but the other one is the elephant’s toothpaste phenomenon created by an instant avalanche degradation reaction of H2O2 to oxygen. This reaction is not entirely catalysed by catalase and peroxidases (which would indeed be too slow) but mostly by stuff like iron ions within yeast which cause a sudden oxygen evolution.

I’m not sure if pH and/or bleach will mess up one or the other reaction to the point of disappointment.

However, too much acid will reduce the efficacy of bleach whilst helping with dissolution of deposits in the bin…
steamedrice

Member
August 19, 2021 at 12:22 am

Perry said:

As far as I can tell, you have no foaming agent in there to trap the gas and make bubbles.
You also have included an oil that will reduce foam.
In the elephant toothpaste experiment they include a surfactant like soap that captures the gas as it’s formed. I’m not sure if the enzyme in the yeast will produce enough gas fast enough but without a foaming agent, all the gas it does produce just goes into the air.

Thank you so much Perry!

My intent of adding drops of essential oil is merely to wet the powders & add a bit of scent to the mix.

What do you suggest that I use to act as binder for the mix?
steamedrice

Member
August 19, 2021 at 12:25 am

Pharma said:

@Perry Yeast is added as catalyst to kickstart decomposition of hydrogen peroxide (H2O2 is what’s originally used in the elephants toothpaste concoction and what’s created when dissolving sodium percarbonate in water). There are other, better, catalysts available such as potassium iodide.

Hi Pharma, thank you for your comment!

Yes, Potassium Iodide is added with H2O2 to create immense foaming. But I read up it will cause yellow fuming, which is not ideal as a household product. Is there anything else that will act as a catalyst as well as potassium iodide?

Will sodium percarbonate with citric acid + foaming agent (ie. SLS, Cocoamidopropyl Betaine) do the trick without yeast?

Thanks again!
PhilGeis

Member
August 19, 2021 at 12:42 am

This may violate the Geneva Convention https://www.icrc.org/en/doc/war-and-law/treaties-customary-law/geneva-conventions/overview-geneva-conventions.htm
steamedrice

Member
August 19, 2021 at 12:45 am

chemicalmatt said:

@steamedrice, there is one basic flaw in that formula of yours: the ratio of percarbonate to citric acid is 4:1, where it should be closer to 2:1, especially with Ca hypo in there. That alone will produce a lot more fizzy. Also, I assume you are using coated percarbonate and hypochlorite? If not you’ll experience constant sublime reduction of the oxygenators to the point where there’s not much left to produce gas on solution/acidification. I used to test formulas like this in sealed f/f/s pouches, and even the coated percarbonates will sublime. Per Perry’s comment, no yeast enzyme I know of will produce gas very fast. I’d delete it entirely - no need for it. He’s also right about the soap. Add some SLS powder to that sucker and see what happens. SLS is peroxide stable.

Thank you so much chemicalmatt! Yes, using coated products.

I’ve revised my formula to as following:
- Sodium Percarbonate 74g
- Anhydrous citric acid 36g
- Calcium hypochlorite 40g
- Sodium Lauryl Sulfate 30g
qs. 180g to fit mold

As Perry mentioned, essential oil will anti-foam. What do you suggest that I use instead to bind it together?

Thank you!!!
Pharma

Member
August 19, 2021 at 4:38 am

You can buy several catalysts (in powder form) of undisclosed composition.

Apart from that: Platinum on charcoal and other lab catalysts as well as powdered blood might not be practical, too expensive, and/or incompatible with hypochlorite… the rest you’ll have to google cause I’d have to do the same.

I don’t see any advantage of combining two gas producing reactions in one cleaning bomb. If you were to rely only on the reaction of acid with carbonate, then you’d have H2O2 left to help with the cleaning which you forfeit when adding yeast or iodide. Besides, all the fun of the latter reaction is that it, if done ‘right’, shoots out of the vessel, high up into the air .
steamedrice

Member
August 20, 2021 at 1:18 am

Pharma said:

You can buy several catalysts (in powder form) of undisclosed composition.

Apart from that: Platinum on charcoal and other lab catalysts as well as powdered blood might not be practical, too expensive, and/or incompatible with hypochlorite… the rest you’ll have to google cause I’d have to do the same.

I don’t see any advantage of combining two gas producing reactions in one cleaning bomb. If you were to rely only on the reaction of acid with carbonate, then you’d have H2O2 left to help with the cleaning which you forfeit when adding yeast or iodide. Besides, all the fun of the latter reaction is that it, if done ‘right’, shoots out of the vessel, high up into the air .

Thank you again replying! Appreciate it.

I was hoping the ‘double’ bubbling reaction will make it foam more. But with my first attempt it failed. I’ll try again without the yeast & with different ratios of Sodium Percarbonate：Citric acid. Hope it’ll turn out good.

Interesting that you mentioned the iron in the yeast reacting with H2O2! Is it sort of the same idea as fenton reaction in pharmacology that I remember studying (ie Metronidazole)?
steamedrice

Member
September 23, 2021 at 11:59 am

Hi amazing formulators & chemists,

As previously mentioned, I’m designing a toilet bowl cleansing bomb that you can leave-in for 30 minutes & will get rid off aged dirty stains.

I have made a few batches of my toilet bomb.
(See attached photo) It performed very close to my expectations! I wanted it to foam all the way up to the rim!

Few observations:
1) Foaming is more intense when NaHCO3:C6H8O7 is closer to 55:45 than 3:1

2) Instead of Bath bombs, I tried to just made it as powder form & it also foams more quickly & immensely. Prob because of higher total surface area?

3) As binder for the bomb, I used Cocamide DEA, as it is sticky & works great as a binder. Is this even practical? No idea…

Few questions I have if anyone can kindly shed some light

1) Will SLS foam more with Capb or DEA?

2) Do I still need Calcium Hypochlorite when Im already using Sodium Percarbonate? Im looking for heavy duty cleaning

3) Should I add TAED as activator for Sodium Percarbonate?

4) Will adding Calcium Peroxide increase foaming as it is an oxygen generator as well as a disinfectant?

5) Which is a better disinfectant for toilet bowls? H2O2, Calcium Hypochlorite or Sodium Dichloroisocyanurate? Or any other kind suggestions?

Thank you all!
Pharma

Member
September 23, 2021 at 7:22 pm

H2O2 is the fastest to act but it’s liquid and always contains >2/3 water.

Isocyanurates are, if I’m not mistaken, ‘slow release’ chemicals and better suited for pools or those tablets which hang in a crate inside the toilet.
steamedrice

Member
September 25, 2021 at 6:02 am

Pharma said:

H2O2 is the fastest to act but it’s liquid and always contains >2/3 water.

Isocyanurates are, if I’m not mistaken, ‘slow release’ chemicals and better suited for pools or those tablets which hang in a crate inside the toilet.

Thank you so much! I just purchased some Calcium Peroxide… doesn’t seem to add foaming?