Non-Chemical Frozen AP

[Marcel]

I was just processing some pins and contacts when I noticed how much of the fine gold power floated in the solution.
I first filtered the finished AP then collected it.
In the filters I found a blueish substance along with the gold foils and particles.
Rinse filter with hot water, part of the substances dissolves, passes trough filter and the rest turns orange.
Rinse filter with HCl and part of the substance disolves and passes trough filter. some grey substance remains, along with the goldparticles.
I still saw very small particle floating. So I decided to freeze the AP and then get the particles.
Put the filtered AP into plastic champagne glasses and let them freeze in a refrigerator.
A dark substance and fine gold powder was trappen in the bottom of the glass. Since it was narrow, it was easy to saw the dark end off and a blue fresh looking frozen AP remained as rest.
Repeated this with about 20 glasses and concentrated the settlements from the bottom of the glasses.

Added the expert from the filters since it looked the same.
After 3 times concentrating I had half a glass with grey substance mixed with gold powder and some larger foil on the bottom. Melted it.

Question now is: What do I have here? There is quite some gold powder that I colleted this way and there still is this grey substance which does not dissolve in HCl and seems to have a similiar density as gold since it always where the gold is.
Some of the grey stuff was able to pass the filter, some not.
How do I go on from here?

 

[lazersteve]

Sounds like it may be silver chloride and the purple color supports this.

Try dissolving the purple powder with 10% ammonium hydroxide and a little heat.

The gold foils will remain behind when the ammonium hydroxide dissolves all of the silver chloride.

Be sure to acidify the ammonium hydroxide after the silver has all dissolved. You will recover the silver chloride as a white curd in the liquid after the muriatic acid is added. This white curd will turn purple when exposed to bright light or sunlight.


Steve

 

[Marcel]

OK, I collected some of the purple grey material from filters, then filtered it trough with 10% ammonia (which stinks like hell).
Poured some diluted HCL into the glass underneath, so every drop that falls imm. is preticipated as white powder (AgCl I suppose) and will be processed to Ag later.
Here a picture of the filtered AP solution that was quite saturated, dark green:

This is how the slowly processing filter looks like when ammonia was added:


What is that yellow material in the filter? The AP was a dark green almost black, saturated one.
It dissolves in HCl, creating a light yellow liquid.

One by one the drops passed the filter and this is what remained: gold plus a dark grey powder:




This AP on the last photo was used but still bright blueish

My question concerns the dark grey powder. Any suggestion on what that my be, (leftover AgCl?) or how to test for it?

 

[lazersteve]

You need more ammonium hydroxide to remove the remainder of the silver chloride. It may take a few passes with heating.

The blue color to the liquid is most likely copper.

Steve