arthur kierski
Well-known member
how can one extract the gold +silver +pd chemically from this mixture of metals tailings?example: 1kilo of this material(i have 30kilos of this material)
copper +silver+tin +pb+pd+au---being 90% and 10% of the rest
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Arthur,
What percentage of each PMs, base metals, and other is the material?
What is the average size of the material?
Steve
What percentage of each PMs, base metals, and other is the material?
What is the average size of the material?
Steve
arthur kierski
Well-known member
i did not specify my thread--it is 90%copper and 10% of the other metals
arthur kierski
Well-known member
steve ,this material is from motherboards which i powdered in a big shreder and then separated by eletrostatic ---the plastic from the metals----i sent 140 kilos of motheboards without the iron connectors and got back today 37 kilos of these metal tailings--i did this because the chinese in brazil are buying these motherboards for 3,5dollars a kilo ,and i deduced that there is a lot of money in these boards(all populated but without the ceramic processors)
Arthur,
35% nitric will be the most direct route to separating the mixture.
The copper, silver, and palladium will dissolve and the gold will remain as a solid.
After filtering the solution, precipitate the silver as silver chloride with HCl or sodium chloride*.
Let settle, siphon, and repeatedly wash the precipitated silver chloride with hot water until the the rinse water no longer shows a blue tint when ammonium hydroxide is added to a small sample of the wash water.
Combine the rinse waters with the nitrate solution and cement the Pd using solid copper.
Filter the powder Palladium and wash repeatedly with hot water until the rinse water no longer test positive for copper with the above ammonium hydroxide test.
Process the gold as usual with AR.
Redissolve the fine Palladium powder in hot HCl and precipitate with ammonium chloride and sodium chlorate.
Convert the silver chloride to metal and* melt the silver as 99% pure.
Cement the copper from the barren copper nitrate solution using iron.
Neutralize and dispose of the iron solution or convert nitrates back into nitric acid.
Steve
* = EDIT
35% nitric will be the most direct route to separating the mixture.
The copper, silver, and palladium will dissolve and the gold will remain as a solid.
After filtering the solution, precipitate the silver as silver chloride with HCl or sodium chloride*.
Let settle, siphon, and repeatedly wash the precipitated silver chloride with hot water until the the rinse water no longer shows a blue tint when ammonium hydroxide is added to a small sample of the wash water.
Combine the rinse waters with the nitrate solution and cement the Pd using solid copper.
Filter the powder Palladium and wash repeatedly with hot water until the rinse water no longer test positive for copper with the above ammonium hydroxide test.
Process the gold as usual with AR.
Redissolve the fine Palladium powder in hot HCl and precipitate with ammonium chloride and sodium chlorate.
Convert the silver chloride to metal and* melt the silver as 99% pure.
Cement the copper from the barren copper nitrate solution using iron.
Neutralize and dispose of the iron solution or convert nitrates back into nitric acid.
Steve
* = EDIT
arthur kierski
Well-known member
thanks steve for the quick reply---i think that i found the solution of extracting pms from motherboards which will help many members from our magnific forum --as always thanks for your help and advice
So Arthur, what percentage is the tin and the lead?
Randy
Randy
arthur kierski
Well-known member
steve;i did as you sugested(hno3 35%) and i am trying 2 days and the solution does not filter---it formed a jelly like paste that makes the filter impermeable---the liquid that passed to the solution does not have(silver--tested with nacl) nor palladium------please give me a sugestion---i found lots of magnetized powder (iron ) in the tailings
arthur kierski
Well-known member
thanks OZ,Mark, Randy and Carlos from Colombia-----it is defintelly a tin compound(metastanic compound)---i have the advantage of having all the metals from the motherboard s together and the disadvantage of this tin compound--- i cannot incinerate this material because of the quantityes (200kilos per month)--i do not have equipment and the metals still contain some plastic and fiberglass (around 5%) which gives terrible smell and toxic fumes whem incinerating------yesterday before leaving my lab ,i did cianide leaching as an experiment and today (saturday) i will go to the lab and see if i got results---if i get the results i will avoid incinerating and then hcl treatment.--- i will pass to you the results--- if not positive results ,i will use ar without prior treatment to eliminate base metals---
Arthur,
The tin/lead as Randy pointed out will cause you the problems you encountered. I was referring to a source material of 90% copper 10% PMs. I should have realized that there would be tin and lead present from your description of the source material.
Tin will dissolve in hot HCl if it is a high enough percentage of the material to be properly exposed to the acid.
Your cyanide approach may be a good route if you get good exposure of the PMs to the cyanide.
The metastannic acid (white jelly) is a real pain and is best handled via incineration as Harold has always pointed out.
Place a small sample of the material in water and stir vigorously to see if the remaining plastics will float to the surface. If they do you can separate them from the metals this way. Once the plastics are removed incinerate the material treat with hot HCl to remove the tin.
Once the tin is removed proceed as I had previously mentioned on the residue.
Steve
The tin/lead as Randy pointed out will cause you the problems you encountered. I was referring to a source material of 90% copper 10% PMs. I should have realized that there would be tin and lead present from your description of the source material.
Tin will dissolve in hot HCl if it is a high enough percentage of the material to be properly exposed to the acid.
Your cyanide approach may be a good route if you get good exposure of the PMs to the cyanide.
The metastannic acid (white jelly) is a real pain and is best handled via incineration as Harold has always pointed out.
Place a small sample of the material in water and stir vigorously to see if the remaining plastics will float to the surface. If they do you can separate them from the metals this way. Once the plastics are removed incinerate the material treat with hot HCl to remove the tin.
Once the tin is removed proceed as I had previously mentioned on the residue.
Steve
arthur kierski
Well-known member
results from the cianide leaching-=1.9grams of pm-----making a resume: i took 1050grams and dissolved in nitric(35%) and the result was that after 2days of suffering,the filtration ended and i was left with 107grams of powder(the tailngs became powder) . I took this powder and did a cianide leaching and the result was 1,9grams of pms-----------1050grams is 2.8% of my material--so the material should give 67grams of pm---------------------
monday i will take another 1050grams and will leach directly with cianide to get with more precision the results-----if the result equals or is superior to the obtained before,which i think will happen ,because i do not know if pd and ag are in the metastanic -nitric----i will then do the cianide process which is quicker-----------thanks all for the support and understanding of mine rather confused english
monday i will take another 1050grams and will leach directly with cianide to get with more precision the results-----if the result equals or is superior to the obtained before,which i think will happen ,because i do not know if pd and ag are in the metastanic -nitric----i will then do the cianide process which is quicker-----------thanks all for the support and understanding of mine rather confused english
arthur kierski
Well-known member
mark,here a fly is a fly----- :wink: :wink:
