Wound up with black solids from my SMB drop

[fermi]

This is my first go at refining. I was trying for a 2 step method with CPU's, fingerboards, and a few cell phone components.

1st step: Soak the broken up gold bearing components in ~15% molar Nitric Acid, I wound up with a blue solution for 1 week and then transferred the solids it 15% molar HCl acid and gave it another week
http://s1056.photobucket.com/albums/t372/fermichan/?action=edit
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=IMG00769-20120217-1736.jpg

Once this step was done I filtered out the HCl and wound up with a beatiful yellow solution
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclb4.jpg

I added SMB to the AuCl/HCl solution and after a few hours I have a black solution:
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclafter.jpg


I am pouring off the clear material, and am getting down to a fine black solid
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=Black-1.jpg&t=1329686903626


What do I do, I am not sure where I messed up and how I can recover from where I am at!

Please help! :!:

 

[martyn111]

From what I can make out from your pictures, it would have been easier to see what was going on if you had used glass instead of the ceramic pot and pictured it from the side, it looks like you may not have messed up, what you appear to have in the measuring cylinder in the last picture is precipitated gold powder, not the cleanest of gold powder but you can easily re dissolve it and precipitate it again to improve the purity.

Edit spelling

 

[patnor1011]

This is my first go at refining. I was trying for a 2 step method with CPU's, fingerboards, and a few cell phone components.

1st step: Soak the broken up gold bearing components in ~15% molar Nitric Acid, I wound up with a blue solution for 1 week and then transferred the solids it 15% molar HCl acid and gave it another week
http://s1056.photobucket.com/albums/t372/fermichan/?action=edit
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=IMG00769-20120217-1736.jpg

Once this step was done I filtered out the HCl and wound up with a beatiful yellow solution
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclb4.jpg

I added SMB to the AuCl/HCl solution and after a few hours I have a black solution:
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclafter.jpg


I am pouring off the clear material, and am getting down to a fine black solid
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=Black-1.jpg&t=1329686903626


What do I do, I am not sure where I messed up and how I can recover from where I am at!

Please help! :!:

You see what I marked red?
Define how did you transferred solids from Nitric to HCl. What did you do before you put everything to HCl, did you incinerate solids?
Are you sure that all base metals were dissolved? Probably not, I can see semi dissolved pins on some CPU in there. Firstly you did not dissolved all base metals what means that most of gold stayed on material when you introduced HCl. Then you created weak AR which dissolved some of you gold and solution appeared yellow but was in fact still with base metals. Your gold or at least some of it will still be on your material on undissolved parts in form of brown, black fine powder.

You can put all solids and all solutions together again. Use heat and try to dissolve whatever metal still present on your material, cement on copper afterwards. Decant, test leftover solution, wash cemented powder and start again this time with cemented powder so less chemicals and smaller beakers will be used .

 

[fermi]

This is my first go at refining. I was trying for a 2 step method with CPU's, fingerboards, and a few cell phone components.

1st step: Soak the broken up gold bearing components in ~15% molar Nitric Acid, I wound up with a blue solution for 1 week and then transferred the solids it 15% molar HCl acid and gave it another week
http://s1056.photobucket.com/albums/t372/fermichan/?action=edit
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=IMG00769-20120217-1736.jpg

Once this step was done I filtered out the HCl and wound up with a beatiful yellow solution
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclb4.jpg

I added SMB to the AuCl/HCl solution and after a few hours I have a black solution:
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=auclafter.jpg


I am pouring off the clear material, and am getting down to a fine black solid
http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=Black-1.jpg&t=1329686903626


What do I do, I am not sure where I messed up and how I can recover from where I am at!

Please help! :!:

You see what I marked red?
Define how did you transferred solids from Nitric to HCl. What did you do before you put everything to HCl, did you incinerate solids?
Are you sure that all base metals were dissolved? Probably not, I can see semi dissolved pins on some CPU in there. Firstly you did not dissolved all base metals what means that most of gold stayed on material when you introduced HCl. Then you created weak AR which dissolved some of you gold and solution appeared yellow but was in fact still with base metals. Your gold or at least some of it will still be on your material on undissolved parts in form of brown, black fine powder.

You can put all solids and all solutions together again. Use heat and try to dissolve whatever metal still present on your material, cement on copper afterwards. Decant, test leftover solution, wash cemented powder and start again this time with cemented powder so less chemicals and smaller beakers will be used .

http://s1056.photobucket.com/albums/t372/fermichan/?action=view&current=stripped.jpg

I poured the Nitric acid through a coffee filter and then took the coffee filter and everything in it and soaked it in HCl. I did not incinerate between steps and there was base metal remaining. I kept the Nitric acid separate from the HCl acid.

Would you recommend that I mix the Nitric acid with the HCl that has had SMB added to it, or should I use the Nitric acid and mix with fresh HCl and then add the solids to this aqua regia?

I appreciate the input and patience so far, I now realize I sould of spent more time reading before starting the process!

 

[fermi]

OK, I decanted off all of the liquid from the black solids and I am starting the nitric acid soak over again with the CPU's and the black solids. I am reusing the nitric acid which has turned blue from the Cu+ cations.

Please let me know if this is not the right path!

 

[patnor1011]

Dont forget that there may be values in your decanted liquid too, put some big piece of copper inside and try to cement any potential values locked in decanted solution.

 

[butcher]

The advice you were given so far is just great; I will add something just to jog your memory.

It looks like you’re on the right path.

Check the nitrate solution for silver and Palladium (cement on copper).

Decant solution from black powder; test the solution with stannous chloride,

Wash black powders using Harold’s washing procedures, and then re-refine the (black) powders in aqua regia (using minimum nitric) or you can use HCl/NaOCl (bleach) method.

After dissolving use few drops of sulfuric to help remove lead, if using aqua regia, you will need to remove free nitric acid (evaporation method or gold button), if aqua regia is used check for and remove any silver (water dilution after evaporation process let sit overnight), silver will precipitate, decant and filter gold containing solution, and then precipitate the gold, recheck solution with stannous chloride.


If you use HCL/NaOCl method, make sure free chlorine is eliminated (heating), any silver will precipitate from HCL/NaOCl solution once cooled and allowed to settle well.
Decant and filter solution and precipitate gold, recheck solution with stannous chloride.

Wash gold powders using Harold’s method for getting gold pure (shining)(general chat).