Refining Golden Foils From Fingers (Aqua Regia)

[72chevel]

Following along to learn the process. I am back at step 1 "bucket of gold leads" thought I had a good grasp but now I am like :shock:

 

[Tzoax]

No need to add smb, mainly when you already added too much of it. Skip smb go for evaporating and then cement values on copper. Cemented powder should be dried and incinerated. Then you may want to leach base metals out of it with warm HCl maybe with few drops of peroxide. Then cemented powders (what will be left of them) can be redissolved in AR. Forget about smb till you do all of this.

Thank You Patnor, I will do that. When we are discussing about cementing, I also have a couple of liters of used acids (HCl + H2O2) that I used several times, the solution is almost black, and I have couple of liters of nitric acid also used couple of times, the color is deep blue. Can You give me a hint what is a best way to cement metals in this two types of solution, and can I collect the remaining powders all together, incinerate, then to use in AR? I thought that when I am anyway gonna do cementing I could do it all together with eventual gold in my other solutions if there is some dissolved gold inside of it (today I will test it with stannous chloride). Thank You.

 

[patnor1011]

There will be nothing in your AP solution. If you set in an air bubbler (aquarium pump) for few hours then it will turn light green again.
Your nitric may contain some silver from solder but it will be very little. Test it to see if there is silver present. Your spent solutions should not contain any value, I presume you tested them when you recovered whatever you were processing.

 

[Tzoax]

I tested the solution with stannous chloride and the result was negative. I will wait a few more hours and I will decant it. So I guess there is no need to cement the powder since there is no more gold in a solution.

 

[heliman4141]

Thank You very much Pantherlikher! I will post exactly what I do, with pictures and measures. Right now I am preparing and cleaning the dishes I will use.
The basic idea is to fill the golden foils with HCl (I will post exactly how much), then I will heat it (not to boiling point) and then I will keep adding a small amount of nitric acid, and observe the process until all golden foils are dissolved.

Bummer Tzoax,
I also have a decent amount of Gold foils & some powder ( both kept seperated in different containers) & at this point you should have ONLY heated with a small amount of Hcl in a beaker containing the foils for a while to remove any stubborn base metals left over, then rinsed/boiled in water at least 3 times then dried it without filtering but instead, just decanting.
After this then you would have been best served to do AR by adding the foils or powder & just covering them slightly with Hcl heated again but not boiling then adding just a few drops of nitric, covering with a pc. of watch glass & observing the reaction. If needed then keep adding just a few drops of nitric JUST until everything was dissolved. Less nitric, less nitric just add heat remember this.
Once that was acheived then add an equal or better volume of distilled water, mix & add a few drops of sulfuric incase any lead/tin is present or add sulfamic solid acid to do same job and also neutralize the nitric. Next would have been to filter it finally & then drop the Gold using a small amount of SMB added as necessary in small amounts until liquid looks clear & tests free of Gold.

Decanting again, then multiple rinses. After this you can melt as usual to a Gold bead, test for fineness & do another drop in AR if its not acid testing up to your desired visual or purity results.
Ive read double dropping it is becoming the norm for 999 purity.

Myself, im waiting till all my excess refining material is in powder form before doing all this again probably by Fall. And yes ill be doing a double drop of the powders then.
AR at the beginning is a real No-No on any e-scrap material no matter how it was obtained, even clean looking foils. As has been said before, most of us spend 99% of our time prepping our Gold in recovery............................................. then 1% is spent refining it......................

My neighbors had just moved in & I had to shut down & sold most of my Nitric then, as luck would have it, the owner of the rentals perished, now everyone has been thrown out & the owners kids are going to sell or let the apartments sit empty so im back refining again. Wish now id have kept my Nitric .................sigh. Down to about a 1/2 liter and I have lbs. of pins & a few lbs. of Gold filled jewelry to incernerate & do also.............May try the Hcl/bleach thing when my nitric is history unless I can get some more at a reasonable price. Duda diesel is not a cheap source...............
Dave

 

[Tzoax]

Thank You very much Pantherlikher! I will post exactly what I do, with pictures and measures. Right now I am preparing and cleaning the dishes I will use.
The basic idea is to fill the golden foils with HCl (I will post exactly how much), then I will heat it (not to boiling point) and then I will keep adding a small amount of nitric acid, and observe the process until all golden foils are dissolved.

Bummer Tzoax,
I also have a decent amount of Gold foils & some powder ( both kept seperated in different containers) & at this point you should have ONLY heated with a small amount of Hcl in a beaker containing the foils for a while to remove any stubborn base metals left over, then rinsed/boiled in water at least 3 times then dried it without filtering but instead, just decanting.
After this then you would have been best served to do AR by adding the foils or powder & just covering them slightly with Hcl heated again but not boiling then adding just a few drops of nitric, covering with a pc. of watch glass & observing the reaction. If needed then keep adding just a few drops of nitric JUST until everything was dissolved. Less nitric, less nitric just add heat remember this.
Once that was acheived then add an equal or better volume of distilled water, mix & add a few drops of sulfuric incase any lead/tin is present or add sulfamic solid acid to do same job and also neutralize the nitric. Next would have been to filter it finally & then drop the Gold using a small amount of SMB added as necessary in small amounts until liquid looks clear & tests free of Gold.

Decanting again, then multiple rinses. After this you can melt as usual to a Gold bead, test for fineness & do another drop in AR if its not acid testing up to your desired visual or purity results.
Ive read double dropping it is becoming the norm for 999 purity.

Myself, im waiting till all my excess refining material is in powder form before doing all this again probably by Fall. And yes ill be doing a double drop of the powders then.
AR at the beginning is a real No-No on any e-scrap material no matter how it was obtained, even clean looking foils. As has been said before, most of us spend 99% of our time prepping our Gold in recovery............................................. then 1% is spent refining it......................

My neighbors had just moved in & I had to shut down & sold most of my Nitric then, as luck would have it, the owner of the rentals perished, now everyone has been thrown out & the owners kids are going to sell or let the apartments sit empty so im back refining again. Wish now id have kept my Nitric .................sigh. Down to about a 1/2 liter and I have lbs. of pins & a few lbs. of Gold filled jewelry to incernerate & do also.............May try the Hcl/bleach thing when my nitric is history unless I can get some more at a reasonable price. Duda diesel is not a cheap source...............
Dave

Thank You Dave, great tips, I learned a lot in past few days, specially on my mistakes and a great help of You guys. Well, I experience this as a practice, when I manage to learn and get some practice I will get my hands on real stuff. For example I collected about 5 kilograms of ceramic cpu's, I can buy e-scrap cheap, and I am calculating and testing which components are best to process. The IC chips and flatpacks looks interesting to me so I will try to process 1.2 kg of mixed chips next week to see approximately yealds of gold. I am sorry about Your nitric.

 

[joubjonn]

Do a search on the forum for a discussion Harold and GSP had on double refined gold. Very cool "heated" discussion on that topic. From 2007 I think. Very good information from two of the most knowledgeable in the world on real world gold refining.

 

[Tzoax]

I decanted and dried out the dust, I get 3.8 grams of pure gold dust (from 5.3 golden foils at a beginning), here is a picture. After this I will boil and rince it couple of times with HCl and water and I will collect the powders. Thank You all very much, I learned a lot thanks to You guys.

 

[heliman4141]

Do a search on the forum for a discussion Harold and GSP had on double refined gold. Very cool "heated" discussion on that topic. From 2007 I think. Very good information from two of the most knowledgeable in the world on real world gold refining.

Oh yea,
I read that one myself .............a very good read..... :mrgreen:
Definatly one of the most interesting oldies ive read to date.
Dave

 

[patnor1011]

Do not forget to check your stannous against known sample of gold bearing solution. Always check is stannous work correctly otherwise it may cost you a lot of money.

 

[Tzoax]

Do not forget to check your stannous against known sample of gold bearing solution. Always check is stannous work correctly otherwise it may cost you a lot of money.

Thank You Patnor, that's very clever idea. The next time I will save some AuCl3 liquid for testing.

 

[Anonymous]

Tzo that gold looks good and well done.

I would recommend searching how to clean it up though because the colour looks to me to have a fair amount of copper left in it.

Then it will look even better 8)

Edit: The rest of your post already said you would do exactly that! My apologies for not reading your post beyond the nice picture mate.

Regards

Jon

 

[goldsilverpro]

No weight or appearance is meaningful until it has been melted.

 

[Tzoax]

Tzo that gold looks good and well done.

I would recommend searching how to clean it up though because the colour looks to me to have a fair amount of copper left in it.

Then it will look even better 8)

Edit: The rest of your post already said you would do exactly that! My apologies for not reading your post beyond the nice picture mate.

Regards

Jon

Hi Jon! I boiled 3 times by 10 minutes in destilled water, then 3 times in HCl, then 3 times again in water. The loss was about 10 percents. Here is the picture.
( I was mixed together the dust from this topic - 3.8 grams, and the dust from my other topic "pins with nitric acid" - 0.5 grams of dust and I process them together. At the end of cleaning process I ended with 3.8 grams, thats about 10 percents of loss).