Sodium percarbonate (2 Na2CO3 · 3 H2O2) instead of H2O2?

[Marcel]

Any experienece and thoughts on using this product (oxygenpulver for fish tanks).
It is cheaper than H202 and it does not have any water in it which would make my AP solution last longer. I only worry about the sodiumcarbonate and the fact that 2 Na2CO3 · 3 H2O2 will develop a a strong alcalic influence.
I have read some threads about it here, but it seems they have used it for some other purpose.
Another point is, that I want to set up an AP container with 5-10l with the lid closed, so no air/oxygen will come in. I have already tested that, but the AP was slowed down until stop because the oxygen was missing. Later I will add a bubbler but for now I would like to know if it is feasable to use it as oxygen source.

Marcel

 

[Irons2]

Sodium Percarbonate is Basic, thus will neutralize your HCl.

 

[butcher]

Percarbonates in acid will produce an awful lot of oxygen at once, especially in warm or hot acid, if you sealed the 5 gallon bucket I do not think it would stay sealed very long before it either blew the lid of split a seam, also all of the oxidizer released from it in the acid would most likely dissolve the fine gold plating, which in the copper II chloride leach we are normally trying to avoid dissolving gold as our goal is to dissolve copper and not touch the gold plating.

I am unsure why your trying to seal your bucket, as if any peroxide or air trying to escape would try and build pressure in the bucket, or the reaction would slow as the air bubbles could not escape solution, or H2O2 or air was not replenished from an air fish tank mini compressor and hose (which is a good way to keep just about the right amount of oxidizer in solution).

If this is because you are wishing to keep the buckets in a shed, why not have an exhaust hose from your bucket lid, a little larger than the hose from your fish tank air supply, the exhaust hose could be routed outside through a hole in the shed wall, if the shed got cold this 5 gallon bucket could sit in an insulated box or cabinet with a light to keep it warm (just be sure you do not create a fire danger getting something too hot with the light, and are safe with the electrical, for safety I suggest a GFCI circuit anywhere you work with acids or liquids, and electricity in your lab.

 

[Marcel]

@butcher:
First of all thank you for your always precise and helpful answers. You and irons2 are right.
I went to shopping with wife and kids and added some of the sodium carbonate to the tank (the AP was 3l 32% HCl + a bit 12% H2O2 + 2 Kg of high grade pins).
When I cam back the solution was neutral, even some SP remained undissolved on the bottom.
So I decanted all liquids removed the leftover SP and filtered the black/green AP solution.
I collected some foils of various sizes but no small particles.
Tested the solution with Stannous (dont know if that can even work for a lye) but it was nothing.
Then I filled two 100ml beaker with the solution and acified them with HCl.
Tested with Stannous again, negative.
I put a copper spiral in one to see wheter anything from gold and above would come down.
The second beaker was added zinc powder incrementally to drive anything out. After the solution changed to light almost opaque green I stopped.
Since copper and gold look very similiar I will check tomorrow by adding Cu(II)Cl and see what or if anything remains. But I suppose it was only copper that came down.
Finally: Sodium percarbonate can create a lot of oxygen and is much cheaper than H2O2 if bough as oxygizer for fish tanks f.i. but will not work as a H2O2 replacement. It will neutralize the solution and end the process.
On that closed lid riddle - I was planning a closed loop system with a electrochemical coppercell that would constantly remove the copper from solution and therefore require much less solution and space and probably could be run inside a building without fume hood and waste.
Open tanks give HCl access to the air´s humidity, which will make the solution aquire water and degenerate over time. So a closed system would be ideal to me.
But that seems to be far away now...
Maybe blowing oyxgen in would be an alternative.