sodium percarbonate

[mamapinky]

I'm calling the experts in on this one, I use the more pure form of sodium percarbonate that I order online. I prefer this to oxyclean because I mostly use powder detergents so I don't want all the added washing soda. I have been informed that sodium percarbonate, breaks down into oxygen and sodium carbonate in the wash, is this true does the 99% pure sodium percarbonate break down into sodium carbonate? Have I been fooling myself into thinking I'm not adding excess washing soda when all along I have been? Thank you all much. Cheryl

 

[dixan]

Sodium percarbonate - regardless of its purity - always breaks down to two molecules of sodium carbonate and three molecules of hydrogen peroxide.
However, hydrogen peroxide is ineffective and weak bleaching agent. You'd better use special product in which activator is added. When hydrogen peroxide is activated with TAED, the bleaching agent is peracetic acid; when activated with NOBS, the bleaching agent is peroxynonanoic acid - both much more powerful than hydrogen peroxide itself.

 

[maylingsmom]

dixan

I may not understand you clearly since chemistry was not my best subject in college but does sodium percarbonate have an activator in it if it is "pure"? Also, can you tell me what TAED and NOBS are?

 

[dixan]

maylingsmom,
When you buy sodium percarbonate, it is only this chemical compound, no activator. Pure means it's free from contaminations (usually sodium carbonate).

When companies make powder detergents with oxygen bleach and products for bleaching and stain removal (like OxyClean) they usually add activators. They do it because hydrogen peroxide - H2O2 - (which comes from sodium percarbonate) is ineffective and weak. In Europe TAED is used; in USA and Asia the activator is NOBS. Search Google for more information. Additionally, catalyst can be used. Catalysts increase the reaction speed between H2O2 and the activator.

Adding sodium percarbonate to the wash doesn't give the effect you are looking for. It decomposes to sodium carbonate and H2O2 so very weak bleaching can be seen.

Adding sodium percarbonate to detergent with activator (like Tide) doesn't make things better. The reaction between the percarbonate and the activator is stoichiometric. This means you need precise ratio between these two components (the best ratio between percarbonate and the activator is 2:1 - 3:1). During the chemical reactions both components are exhausted. Using percarbonate will lead to excess of H2O2 which will not react with anything, because the activator is exhausted.

Using percarbonate is useless and a waste of money. For best results, find product with activated bleaching system.

 

[mamapinky]

I have read quite a few posts where Launderess has recommended using a more pure form of sodium percarbonate, because oxyclean is so loaded with sodium carbonate, which is not needed or desired if using powdered detergent. Now its being said sodium percarbonate is a waste of money...I'm confused. Is a more pure sodium percarbonate a waste of money?? And does it turn into sodium carbonate which is just defeating the purpose I use the more pure form? I hope Launderess can jump in here, I could really use that expert advice...thank you Cheryl

 

[dixan]

As I said, sodium percarbonate breaks down to two molecules of sodium carbonate and three molecules of hydrogen peroxide. Pure or not pure, this is the end result.
Pure means it's free from contaminations.

I also explained why it's a waste of money - hydrogen peroxide is weak and ineffective bleach. You can use H2O2 to directly treat the stains - most of the stain removers in liquid form or sprays contain H2O2. In wash (without activator) it doesn't work good at all. That's why activators were invented.

 

[mamapinky]

Perhaps more laymens terms would help me understand, which I would very much like to understand this.

 

[dixan]

I don't understand why are you adding sodium percarbonate to your wash. What is the purpose? Why don't you buy good stain remover with activated bleach system. Tide has great products with perfect ratio between persalt and activator. You will be pleased with the results.

 

[dixan]

Which part you don't understand, mamapinky?

Sodium percarbonate is sodium carbonate+hydrogen peroxide in one. Two molecules sodium carbonate and three molecules hydrogen peroxide are bond together.
In contact with water it ALWAYS decompose to sodium carbonate and hydrogen peroxide.

 

[launderess]

Only Oxygen Bleach Containing Products With Activators

In USA are those sold by P&G (Tide, formerly Biz, etc....)

Unlike Europe where the patents for TAED have long expired thus leaving anyone to add that activator to their oxygen bleaching systems P&G has kept the patents for sodium nonanoyloxybenzenesulfonate (NOBS) locked up. P&G also uses this technology in their automatic dishwashing detergents.

You will not find a single American domestic laundry product with an activated bleaching system outside of those made by P&G unless the use TAED. Ecolab sold an activated oxygen bleaching system for commercial laundries for instance but it used TAED, not NOBS.

That being said anyone can add sodium percarbonate or perborate to their laundry detergents, boosters, stain removers or whatever, it just won't have the same capabilities of an activated system.

 

[dixan]

Well, now you have Persil pearls and it's great bleaching system.
Stain removing powders and packs from Tide are formulated virtually without compromise.
Why pure percarbonate? There is no point. They sell it for laboratories not to use it in your washing machine.

 

[mamapinky]

Sorry what I don't understand is the many posts where Launderess has stated its better to use pure sodium percarbonate, oxygen bleach, instead of using oxiclean because oxyclean has such a large amount of sodium carbonate in it. Yet now I'm learning pure sodium percarbonate won't even activate so it would be worthless.

 

[dixan]

"Yet now I'm learning pure sodium percarbonate won't even activate so it would be worthless."

No, I didn't said that. I said that in contact with water it releases hydrogen peroxide which is not effective bleach. That's why good detergents contain activator. The activator transforms hydrogen peroxide into much more effective bleaching agent.
It's useless to add sodium percarbonate in your wash, because you don't get effective results. You'd better use good quality booster like Tide. The results will be much, much, much better.

 

[mamapinky]

Dixan I appreciate you taking time to help me understand this...what about oxiclean? Would that also not be effective? I have been using 99% pure sodium percarbonate, because of all the posts the Launderess has posted that its a better choice compared to oxyclean with its high amount of sodium carbonate. I know there's a lot of other folks here that use the more pure sodium percarbonate. ..I trying to understand why if its not really effective bleach, why it has been recommended by Launderess here who in my opinion is a genius when it comes to these things, and why it is so popular here as a oxygen Bleach. Thank you much Dixan....Cheryl

 

[maylingsmom]

So help me out with this. Let me see if I understand this. Sodium carbonate is also known as washing soda. Sodium percarbonate "decomposes to sodium carbonate and H2O2." So once sodium percarbonate is added to water, you can't stop it from changing to sodium carbonate and H2O2. Do I have that right?

 

[launderess]

Bleach activating systems came about out of the energy crisis of the 1970's among other reasons. Both NOBS and TAED activate sodium perborate (the then common oxygen bleach in laundry products) so it worked at lower temperatures.

Sodium perborate on its own will bleach but requires temps from a or >140 to really get going. In Europe with all that boil washing and or machines that self heated to temps from 120F to 200F pure sodium perborate wasn't a problem. But again in order to cut energy use bleaching activator (TAED) came along. So now laundries and housewives could get "boil wash" bleaching results at lower temperatures.

On this side of the pond oxygen bleach (again most sodium perborate) was sold as "color safe bleach" because again it takes high temperatures to really get the stuff to work. No one is going to wash colors at 140F or above so the bleaching power was reduced. However it still gave adequate stain removal and other properties wanted from a "safe" bleach. P&G developed NOBS for use with the dilute qualities of American laundry machines (mostly then top loaders) that and or soaking. Biz originally morped from a enzyme pre-soak to an oxygen bleach with an activated perborate system. Oxydol also had a bleaching system (first just sodium perborate then activated). Finally P&G put all their eggs into one basket and came up with "Tide with Bleach". That product as fitting P&G's and America's top laundry detergent had the refined NOBS activated bleaching system and P&G has never looked back. It is only recently that Gain and other powdered detergents have begun sharing some of Tide powder bleaching systems.

Sodium percarbonate OTOH is known as the "cold water oxygen bleach". This is because it is powerful on its own to work even in cold water. It may take longer but unlike sodium perborate the stuff will work in warm, lukewarm and even cold water.

In the EU due to worries and over boron and restrictions on borates laundry and automatic dishwasher products began to move from sodium perborate to sodium percarbonate. Technically sodium percarbonate does not require the addition of an activator. However both NOBS and TAED combine with oxygen bleaches to form peracetic acid which is not only a powerful bleaching agent but disinfectant as well.

So when you see boxes of Persil or Tide Coldwater powders stating they can effectively clean and bleach at temps of 20c or 30c, now you know. The addition of an activated oxygen bleaching system based on sodium percarbonate.

Personally if doing a load of whites or anything else at temps of 100F or above just add pure sodium percarbonate. Do this especially when using liquid or gel detergents because they do not contain bleaching agents. Sodium percarbonate on its own is far from useless. You just have to know what you want to do.

 

[dixan]

"So once sodium percarbonate is added to water, you can't stop it from changing to sodium carbonate and H2O2. Do I have that right?"

Yes, you can't stop the decomposition. That's why you need to keep it in dry place.

* * *
Color safe bleach... Cold water oxygen bleach... Just trade slogans. Marketing.

Both sodium perborate and sodium percarbonate in contact with water release hydrogen peroxide. Sodium perborate however is more stable so you need more time for it to dissolve and release the peroxide.

Yes, sodium percarbonate quickly dissolves in cold water. Yes, it will release H2O2 in in warm, lukewarm and even cold water, but H2O2 is an inefficient bleach in warm, lukewarm and cold water. You need high temperature and even then it's weaker than peroxy acids.
Sodium percarbonate do require the addition of an activator if one wants effective bleaching action. If you want some H2O2 in your wash water, then it's OK to add it.
Yor are right: "You just have to know what you want to do."

 

[dixan]

mamapinky,
I don't know the ingredients of OxiClean. I can't find ingredients list. Similar cheap European products contain sodium carbonate, sodium percarbonate, silicate and non-ionic surfactant. Such products have some positive effects in stain removal mainly because they increase the pH of the solution and add some more surfactant. However, products with activator blow away that cheap stuff. They are more expensive (because the activators are expensive), but work much better.

I don't know why it has been recommended. The question is why do you use it? What does it make for you? You see, when you use sodium percarbonate without activator, you have ineffective bleaching only when the temperature of the solution is above 55-60°C. Yes, it is not completely useless as it has some bleaching and disinfecting properties in high temperatures and high pH. Product with activator on the other hand gives you very strong bleaching from the moment it dissolves and the chemical reactions between the components begin.

OK, you can use percarbonate and it will probably remove some light bleachable stains but if you want to keep your whites white for a long time you need effective bleaching system.

 

[mamapinky]

Launderess, I do use pure sodium percarbonate in water temperatures of 130 and above for whites only that includes white towels and white bedding., I don't use it so much for stain removal as I do its bleaching and whitening properties. I've had excellent results with keeping whites dazzling whites this way. I used to use Oxiclean but didn't like paying for the grand amount of washing soda in that product and being that I use powder detergent most of the time didn't want all that added sodium carbonate. I do use Tide with Bleach, but since I like to switch things up and use different detergents in my stash powderes and liquids that don't have a bleaching system I use sodium percarbonate. I have read a lot here about using pure sodium percarbonate and not wasting money on products like oxyclean that have 50% or better washing soda, which when using powdered detergent isn't wanted due to the host of problems too much of the stuff can cause. All in all I have to say that following the Launderess' s recommendation of using pure sodium percarbonate has worked magic on my whites, and I'm not paying for a bleaching booster product that has more washing soda than actual product. Thank you all for your advice its appreciated. .Cheryl