Hydrometallurgy: Leaching in Heap, Vat, CIL, CIP, Merrill–Crowe, SX Solvent Extraction

Hydrometallurgy: Leaching in Heap, Vat, CIL, CIP, Merrill–Crowe, SX Solvent Extraction

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How to recover precious metals from the spent catalyst used in the manufacturing of lubricants? (7 replies)

S
Seeker
1 month ago
Seeker 1 month ago
Somebody, please help me! 
I want to know about the recovery of precious metals from the spent catalyst 
used in the manufacturing of lubricants.
Thanks in advance!
SmartDog
1 month ago
SmartDog 1 month ago

Of course it depends on the catalyst and what metals are in the catalyst. But the general (simplified) process would be first to burn off any carbon residue on the surface in a high temperature calcination stage (either a rotary kiln (direct fire) or rotary calciner (in direct fire)), then pulverize or grind the material followed by a series of hydrometallurgical steps (leaching and electrowinning) to produce the metals.  Then there is the sludge processing to dry and dispose of the main carrier material (probably 90+% of the material).

S
Seeker
1 month ago
Seeker 1 month ago

Thanks for your help!

S
Seeker
1 month ago
Seeker 1 month ago

Calcination requires a big setup and I want to do it on a small scale. 

I want to recover gold and silver from this. Is it possible to recover these metals from it 

with the addition of certain chemicals (precipitants) without burning off the carbon? 

Can we get metal oxides from it by adding NaOH to it? 

Thanks! 

SmartDog
1 month ago
SmartDog 1 month ago

Most of the lixiviants for precious metals (think cyanide) are readily absorbed by carbon.  This requires removal of any carbonaceous material before processing.

In your first post you did not mention the amount of material you were trying to process.  A scaled down process using ovens and small vessels is always possible.  Should also note that the amount of precious metals in the catalyst is probably less than 1% of the volume.  

Unless this is for a pilot/test facility it is doubtful if it would be economical.

S
Seeker
1 month ago
Seeker 1 month ago

Thanks for your reply. I really appreciate your cooperation. I want to process 500 hundred liters of it now. Can it be recovered through activated carbon also?
Another thing is that I have a gas-run closed furnace in which I melt copper and some precious metals and I can burn around 30 liters of catalyst at one time using a high-grade stainless steel pot. This furnace is completely closed from the top also.
And its top cover has a hole in the center through which some flames come out. The smoke produced during melting is burnt inside it.
But my concern is that during burning this catalyst produces some hazardous gasses, will those gasses also be burnt during the burning process inside the furnace?
Regards
Seeker

SmartDog
1 month ago
SmartDog 1 month ago

The use of activated carbon for gold and silver recovery is one method of stripping the gold and silver from a cyanide based lixiviant.  But you still need to get them out of the catalyst.  

The issue with the furnace is dependent on what type of catalysts you have and what lubricants it was used on.  Different catalysts have different basic carriers and they react differently to heating.  The same for lubricants.  None of this can be answered with general comments.

S
Seeker
1 month ago
Seeker 1 month ago

Thanks for your quick reply.

This catalyst was used by the company that manufactures engine oils.

So, can its hazardous gasses be burnt inside the furnace that I am supposed to use?

Thanks!


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