Well I and I’m sure many others wish you well and hope you succeed, please keep us informed as to your progress and I’m sure others will chip in with help as things proceed.
pH for cementation
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nickvc said:
No worries, I appreciate the support. Its a steep learning curve
After thinking about Goran's comment on the solubility of Palladium in Copper Chloride I think my next run of experiments will be to precipitate from the leach solution using Ferrous Sulfate then attempt to precipitate any Palladium before cementing the rest of the solution with copper.
Until I have the extraction and separation of the metals from the ores sorted out I'm going to concentrate mainly on smelting the Chlorargyrite and mining.
Cheers Wal
Based on the reactivity series, copper should really only drop mercury, silver, gold, and PGMs from a solution with those metal dissolved in it. The other metals that are more reactive will not be reduced to their metallic form by the copper metal. As Göran posted, too high of a pH and hydroxides will start to precipitate even without the addition of copper metal.
So, why not drop the gold, then add copper to drop the metals listed above and then refine the resulting black powders? If your palladium is not concentrated enough in solution during the recovery process, it will be challenging to precipitate clean Pd. Not sure how well DMG would work for dropping Pd from the dilute solution.
geedigity said:
Up until these experiments that is what I had been doing with every batch, dropping the Gold first with Ferrous Sulfate then cementing with Copper and collecting the black powders to refine later.
The thought to try to precipitate any Palladium before cementing with Copper was in relation to Goran's remark that Palladium could be soluble in Copper Chloride solutions.
I'm assuming that would mean some Palladium could be held in solution as the Copper content increased and the solution turned blue
Cheers, Wal
I wouldn't worry about the palladium. It represents less than 0.5% of the value according to your assay.
If you lose just a percent extra of silver or gold because you try to get the palladium first then you have lost more than any palladium you would recover.
If you have a working method, use that and then send in a sample of the tailings when you have recovered all you can. This will tell you what values you missed and you might adjust your process from that.
Göran
If you lose just a percent extra of silver or gold because you try to get the palladium first then you have lost more than any palladium you would recover.
If you have a working method, use that and then send in a sample of the tailings when you have recovered all you can. This will tell you what values you missed and you might adjust your process from that.
Göran
anachronism
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Frankly if I had a claim like this that assayed at the figures you suggest I would be concentrating on it.
anachronism said:
Maybe I worded that wrong, its a time issue at the moment. In a few months the wet season starts and I won't be able to mine once its waterlogged.
That's why i'm concentrating on mining, I still spend around 4 hours a day on the experimenting with recovery methods and learning refining processes.. Not to mention the research here.
I'm not sure what sleep is anymore :lol:
g_axelsson said:
Thanks Göran,
Although I am getting good results so far I always feel like I could do things better.
Cheers Wal
Many if not all ores require a compromise somewhere in recovering values so perhaps Göran has hit the nail on the head,the value in the metals is largely gold and silver so concentrate on them and perhaps research if there is a method to concentrate the palladium and if so simply send to another refinery Whalen you have decent amounts.
nickvc said:
OK, if I cement out the copper using Iron I should eventually have a concentrate that I can recover any Palladium from later
Yes, you could drop out Pd using iron, but you will drop everything less reactive than iron including Cd, Co, Ni, Sn, Pb, Sb, As, Bi, Cu and then also Hg, Ag, Pd, and Pt. Theoretically, of course.
So, why not just use copper and limit your metals to Hg, Ag, Pd, and Pt?
geedigity said:
All the Gold, Silver, the bulk of the Palladium and other pgm's have hopefully been removed from the solution already before cementing with Iron.
I have tons of material to process, I'm just hoping to recover any Pd that remains in what's left of the leach solution by using this step and reprocessing later
Cheers Wal
That sound reasonable. You can always melt down the copper into anodes and run it in a copper cell. The palladium, gold or silver present ends up in the anode slime.fishaholic5 said:
And it's a good way to remove a toxic component (copper salts) from your waste.
I do it with all my waste and saving the copper powder to refine sometime in the future when I have access to a suitable furnace.
Göran
Thanks,
I've decided to drop the pH to close to 1.5, I have metal crystals growing in the last stages now at pH2.
I'll keep the experiment running alongside the cementations with the solutions from dropping the gold first with Ferrous Sulfate for the next few months until the wet season.
It definitely reduces the amount of toxic gases produced in comparison.
Cheers Wal
I've decided to drop the pH to close to 1.5, I have metal crystals growing in the last stages now at pH2.
I'll keep the experiment running alongside the cementations with the solutions from dropping the gold first with Ferrous Sulfate for the next few months until the wet season.
It definitely reduces the amount of toxic gases produced in comparison.
Cheers Wal
I solved the plating issues by increasing air flow to the bubblers, the increased agitation gives me a black powder now.
Cheers Wal
Cheers Wal
That is indeed a terrific fund you have made!
I personally have discoveries where I too am in need of discovering a scientific method for dropping out the pm/ pgm content free from the other metals in the mix. Here's one example:
I personally have discoveries where I too am in need of discovering a scientific method for dropping out the pm/ pgm content free from the other metals in the mix. Here's one example:
Cool, it looks pretty interesting.
I'm not sure how useful this is but I have a couple of thoughts.
I've moved away from pressurised leaching due to the dangers and the fact that PGM recoveries appear to be better for me at a near neutral pH.
The high Iron content in your ore will mean that once the iron content in a Chloride leach solution gets too high the PM's and PGM's will start to drop again unless you use enough leach solution to chlorinate all the metal content of the ore. This can be minimised by shorter leach times but this will also limit the PGM's recovery. Salt in the leach solution will also help keep the metals in solution.
I I have little experience with Rhodium but I've learned that it will dissolve in a Chloride leach if finely divided (thanks Harold and Lou) Most PGM's particles in ore are micro particles so in theory it should dissolve.
PGM's in ores often respond to magnets, it may be possible to separate the bulk of the PGM's content with the iron as well as a percentage of the Gold that contains PGM's or is bound up with the iron and process it separately. Gravity separation may help obtain a concentrate containing most of the values too. I'm still experimenting constantly with methods to reduce the amount of material I actually have to leach.
The Silver and Lead will stay in the ore residue from a Chloride leach, Lead Chloride can be removed with hot water and the Silver Chloride converted to Silver using dilute Sulfuric acid and Iron. You then have to work out how to recover it from the residue.
Chloride leaches on Silver containing ores need to be agitated or rotated constantly to stop the Silver Chloride passivating the other metal particles.
I'm not sure of the effectiveness of Cyanide leaching on Rhodium or its adsorption onto Carbon. Deano or others here have a lot of experience with complex ores and recovery methods. It may be worth exploring as an option for the recovery of the metals on a mining scale as may smelting with Copper as a collector if the values can be concentrated and recovering the Silver, Gold and PGM's during the refining process. If there is enough Gold in the concentrate it should theoretically pick up the Rhodium and other PGM's.
Just thoughts, I'm no expert and still learning and experimenting as I go... A lot of what I know is from the forum anyway and the thing I do best is digging holes
I'm not sure how useful this is but I have a couple of thoughts.
I've moved away from pressurised leaching due to the dangers and the fact that PGM recoveries appear to be better for me at a near neutral pH.
The high Iron content in your ore will mean that once the iron content in a Chloride leach solution gets too high the PM's and PGM's will start to drop again unless you use enough leach solution to chlorinate all the metal content of the ore. This can be minimised by shorter leach times but this will also limit the PGM's recovery. Salt in the leach solution will also help keep the metals in solution.
I I have little experience with Rhodium but I've learned that it will dissolve in a Chloride leach if finely divided (thanks Harold and Lou) Most PGM's particles in ore are micro particles so in theory it should dissolve.
PGM's in ores often respond to magnets, it may be possible to separate the bulk of the PGM's content with the iron as well as a percentage of the Gold that contains PGM's or is bound up with the iron and process it separately. Gravity separation may help obtain a concentrate containing most of the values too. I'm still experimenting constantly with methods to reduce the amount of material I actually have to leach.
The Silver and Lead will stay in the ore residue from a Chloride leach, Lead Chloride can be removed with hot water and the Silver Chloride converted to Silver using dilute Sulfuric acid and Iron. You then have to work out how to recover it from the residue.
Chloride leaches on Silver containing ores need to be agitated or rotated constantly to stop the Silver Chloride passivating the other metal particles.
I'm not sure of the effectiveness of Cyanide leaching on Rhodium or its adsorption onto Carbon. Deano or others here have a lot of experience with complex ores and recovery methods. It may be worth exploring as an option for the recovery of the metals on a mining scale as may smelting with Copper as a collector if the values can be concentrated and recovering the Silver, Gold and PGM's during the refining process. If there is enough Gold in the concentrate it should theoretically pick up the Rhodium and other PGM's.
Just thoughts, I'm no expert and still learning and experimenting as I go... A lot of what I know is from the forum anyway and the thing I do best is digging holes
This are microscope pics of the dried powder obtained from these cementation experiments.
Some more Ore pic's
Gold enrichment zone. This can be smelted as is
