What might be the blue sediment after AR treatment

[vyper]

Im probably be way way wrong here but it sounds like theres some excess copper somehow. When very dilute copper solutions looks a light blue color. When concentrated ammonia is added it turns a violet color as shown in the photo. This is called tetraamminecopper(II) chloride. I dont know if this is what it is but is the only thing I can think of although I dont know why it wouldnt dissolve in nitric. Like I said Im probably wrong but figured Id throw in my dos centavos.

The blue on the left is a dilute copper solution the purple is the color when ammonia is added.

Scott

*edit - typing errors

 

[bee]

Steve,
i process about 200 pounds Pentium pro and mixed ceramic CPU,s my process is simple first i boil the load into 50/50 HNO3 after strong heat for three hours any base metal gone oh sorry to mention i separate all the tungsten gold plated tops, donot add them into HNO3 bath and when all BM gone i add all tungsten GP heat sinks along the BM removed CPU, next step is aqua regia donot add heat just use hcl and then add the hno3 on large batches 25ml or small batches 5 ml.
on strong stir you ,ll found there is no GP empty pin shell and reaction is complete use always excess hno3 and make sure no reaction is occur then pour the solution give two washes or more until residue looks colorless, gravity filtration is best or let it settle for 24 hours when every thing settle syphon as much as you can and rest should be filter add sulfamic acid remove excess nitric by sulfamic acid or low heat and precipitate gold by SMB .
i observe some time little tungsten oxide otherwise the tungsten heat sinks are same looks like the Steve pictures.
so personal experience if you separate the tungsten GP heat sinks and add them into aqua regia! very little tungsten dissolve.
thanks
bee

 

[lazersteve]

Bee,

You mention removing the tungsten "heat sinks" before processing in nitric acid, then adding them back into the AR. How are you removing the "heat sinks" from the cpus?

For the record, my photo above is of tungsten heat spreaders, not heat sinks. They have not been in any AR.

Anodized Aluminum and Other Heat Sinks:

Steve

 

[bee]

sorry Steve,
fast typing mistake guys Steve is right its tungsten GP heat spread i am not editing my above post so any one can see what Steve mentioned.
and there is no reason to add heat sinks into your any batch as they are aluminum.
thanks
bee

 

[bee]

here is the picture of GP tungsten heat spread.
tungsten heat spread are easily recognized. they can easily break into pieces.
thanks
bee

 

[Alentia]

Bee,

Not sure why you are braking them in pieces and how you remove foils from them.

HNO3 treatment separates "W "spreader from CPU and foil, than easily removed by hand (in glove) after wash and before treating with AR.

 

[lazersteve]

Bee,

Not sure why you are braking them in pieces and how you remove foils from them.

HNO3 treatment separates "W "spreader from CPU and foil, than easily removed by hand (in glove) after wash and before treating with AR.

My point exactly. I find it results in an AR solution that is not nearly as much trouble to filter and precipitate. As an added side, you get to keep the tungsten heat spreaders intact.

Steve