AP on my way

[VolkD]

Perhaps it can be done cold?

I don't know, I'll have to do some research. Right now the outside temperature is around 5°C. Not exactly work-friendly.

 

[VolkD]

My setup. The beaker contains hydrochloric acid, copper chloride, and 30g sodium persulfate. I use an aquarium pump to inject air. The pump is on the box so that it is higher than the liquid in the beaker; this way the liquid cannot get into the pump.

 

[VolkD]

I cut the printed circuit boards into smaller pieces. This way there is more space between the pieces and the liquid flows better around them. The printed circuit boards are gold plated and not soldered.

 

[VolkD]

I prepared 100g of sodium persulfate. This doesn't mean I have to use it all. I will add it as needed.

 

[VolkD]

After 40 minutes, gold leaf is already visible in the liquid. I don't know if the photos show the time of creation. That would mean a lot in this case.

 

[VolkD]

Another look at the glass from above. You can see that most of the gold plating is still on the printed circuit boards.
I turned off the aquarium pump to take this shot.

 

[haveagojoe]

Bravo! Encouraging stuff, this could be a significant breakthrough for us Copper Chloride fans - the "VolkD method"!

 

[VolkD]

Of course, I'm not entirely sure. I'm afraid that the thing would dissolve the gold anyway. It turns out that the gold in this mixture does not melt, but due to the strong source of bubbles, the gold foils break into very small particles. Since I don't have good filter paper, there is a possibility that these particles could escape through the filter. To avoid this, I decided to do an intermediate filtration.

I took all the circuit boards out of the solution and filtered the solution. In the photo I am near the end. There is still a lot of gold plating.

 

[VolkD]

There is a lot of gold foil visible almost at the bottom of the glass.

 

[VolkD]

There's even more gold foil on the filter. After filtering, I poured all the liquid back into the working beaker. I added some fresh hydrochloric acid and a little sodium persulfate. Of course, it's not possible without bubbles.

 

[haveagojoe]

Does it bubble from the reaction? Or just from heating?

 

[VolkD]

I put what was left on the filter into a special beaker.I must say that I was pleasantly surprised when filtering, because the filtering went quickly and without any problems. I didn't need any vacuum at all. This is probably because I didn't have any impurities, just copper and gold.

 

[Yggdrasil]

View attachment 67312
There's even more gold foil on the filter. After filtering, I poured all the liquid back into the working beaker. I added some fresh hydrochloric acid and a little sodium persulfate. Of course, it's not possible without bubbles.

The most likely reason for the foils to disintegrate is due to its lack of thickness.

 

[VolkD]

Does it bubble from the reaction? Or just from heating?

Because of the reaction. But I find that it could probably be done without, since the main oxidant is sodium persulfate.The whole thing is still in the testing phase, I have to try it without, but the persulfate consumption will probably be higher.

 

[VolkD]

The most likely reason for the foils to disintegrate is due to its lack of thickness.

Very likely. But it falls apart when you throw bubbles. I should make a video. Of course, I don't expect much gold.

 

[haveagojoe]

Because of the reaction. But I find that it could probably be done without, since the main oxidant is sodium persulfate.The whole thing is still in the testing phase, I have to try it without, but the persulfate consumption will probably be higher.

Oh yea I forgot you have an air bubbler in there too. I would imagine it would be effective without that, it's probably mostly just stirring things up rather than helping with the oxidation.

 

[VolkD]

Oh yea I forgot you have an air bubbler in there too. I would imagine it would be effective without that, it's probably mostly just stirring things up rather than helping with the oxidation.

A little bit certainly helps with oxidation. It is very important to constantly stir the solution. This way the concentration is the same everywhere.

 

[haveagojoe]

A little bit certainly helps with oxidation. It is very important to constantly stir the solution. This way the concentration is the same everywhere.

Yea I mean the bubbler is mostly helping to move the solution around rather than adding oxygen from the air. I imagine nearly all of the oxygen will be from the persulfate, I don't think the bubbler could add more. I would be really interested to see how it works cold with no bubbler and just occasional stirring by hand, by comparison to your current setup.

 

[Yggdrasil]

Yea I mean the bubbler is mostly helping to move the solution around rather than adding oxygen from the air. I imagine nearly all of the oxygen will be from the persulfate, I don't think the bubbler could add more. I would be really interested to see how it works cold with no bubbler and just occasional stirring by hand, by comparison to your current setup.

The point of the bubbler is to supply just enough Oxygen to let the Copper Chloride rejuvenate.

 

[haveagojoe]

The point of the bubbler is to supply just enough Oxygen to let the Copper Chloride rejuvenate.

Yes I know but this is quite different to the usual Copper Chloride etch, OP added a pretty large amount of persulfate, I'd say there's quite likely enough oxygen available to carry it through. Maybe I'm wrong, I don't know. It seems more like the original approach of "AP", but we could never add that much peroxide without dissolving the gold as well.