Pgm refining

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gulammohd

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Only for educational purpose.
For example if , i have 60%silver , 10% palladium , 5% platinum ,20% gold and remaining other pgms.
First i will dissolve silver and palladium as well as platinum in hot concentrated nitric acid but other metals will not dissolve -filter- then precipitate silver with hcl and palladium with dmg then i will add zn or aluminum to precipitate remaining all metals from solution .after that melting zn precipitate and undissolved residue- granulate- dissolve in aqua regia-filter - so2 gas, copperas, for gold precipitation and ammonium chloride for platinum ...
Will this method work or not if not then what problems i will face ... Please reply ..
 

orvi

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In theory it will work. Remember that all separations of PGMs aren´t 100%, and even if you do use selective agent like DMG on palladium, you cannot get pure Pd precipitate at one go.
Mixture of PGMs together with AuAg is fairly complicated, and it is not sure from the start how it would behave in nitric acid - meaning that if you dissolve all platinum, or just a part of it. If it form some intermetallic phases, or grains with higher concentrations of PGMs that tend to not dissolve in nitric etc... With this composition, it should go relatively OK, but as significant ammount of Pd and Pt is present, that will slow the reaction. Ferrous sulfate should perform better than SO2 in terms of purity of dropped gold.

You need to try out, I cannot see anything logically incorrect. But I will wait for few more people to give their opinion :)
 

gulammohd

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I've Precipitated palladium from nitric solution many times with dmg with upto 97% purity. but in that cases platinum was not present ...
What will happen if there will platinum ..
 
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Yggdrasil

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I've Precipitated palladium from nitric solution many times with dmg with upto 97% purity. but in that cases platinum was not present ...
What will happen if there will platinum ..
Platinum will to some degree follow the Pd if I'm not mistaken, the same goes the other way with Ammonium Chloride and Pd but even more I seem to remember.
I think Sreetips/Kadriver has some videos regarding this.
 

4metals

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Another option would be to increase the silver concentration with cement silver to get to 90% and run it in a silver cell. The Palladium will enter the solution and need continual removal using a Dimethylglyoxime filtration circuit but the other PM's will end up in the slimes for processing as they accumulate.
This is a strange alloy in your educational example, no base metals. It could prove easier than one might think to process electrolytically.
 

gulammohd

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Another option would be to increase the silver concentration with cement silver to get to 90% and run it in a silver cell. The Palladium will enter the solution and need continual removal using a Dimethylglyoxime filtration circuit but the other PM's will end up in the slimes for processing as they accumulate.
This is a strange alloy in your educational example, no base metals. It could prove easier than one might think to process electrolytically.
Sir. There is a process to remove base metals with cupellation.
 
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4metals

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Because of the lead fumes and the disposal of the bone ash material which absorbed all of the lead and base metals this process is not used on a scale large enough to require setting up a silver cell.
We have had threads on the forum where we discussed video's made at a "refinery" in India (I believe) where they were doing cupellations on a large scale but it did not appear to me to be sustainable. Not from the sustainability aspect of producing the doré, but from the sustainability aspect of keeping the employees alive.
 
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