PGM recovery with AR leaching. pics

[kjavanb123]

All,

Rh refining,
After addition of soda ash, lye, and baking soda, I let it cool overnight and got the following solution.


Diluted the above solution with water and heated it up. filtered it and got the following.


Waited for hrs but no yellow Rh powder formed, so i saved the solution for later on. As i am processing the other half of the honeycomb.

Pd salt,
After some losses in the Pd solution due to human error, I weigh the pure Pd salt from one honeycomb, about 1.5grams. I haven't done incenration which will be done tommorow, but some of the solution after addition of ammonia and filtering and addition of HCL doesn't form that yellow canary. why is that?


Also, after zinc cementation of the solution from above pic, i dissolved the black powder in AR, heated, denoxx, and added saturated ammonium chloride, after few secs, got this which make me think is this Pt with Pd contamination? After I dissolved the filtered red powder into ammonia, filtered the clear yellow part, there was some yellow powder residue which was dissolved in HCL.


This is after i added sodium chlorate to the already added ammonia chloride solution.


Questions, why adding HCL to filtered ammonia and Pd salt solution, it stays yellow and no powder forms?

Thanks
Kev

 

[lazersteve]

It has to do with the volume of the solution.

The Pd salt precipitated from thew concentrated solution, not the diluted one.

Steve

 

[kjavanb123]

Steve,

in processing of dissolving Pd salt in ammonia, more ammonia should be added? I have done this many times, this is the only time it didn't produce the Pd canary salt.

Kev

 

[lazersteve]

No. The difference may have been the amount of water in the solution.

I've had this happen too. When it does happen I do what you did and zinc it out and start over. You can also evaporate the yellow solution down own until the yellow Pd salt precipitates out.

Steve

 

[solar_plasma]

stannous result after 30mins of boiling in AR.jpg (115.79 KiB)

Has it really to be boiled or only heated? And if boiling is right, would refluxing be ok?

 

[goldenpuncture]

after using zinc! black poder is dissolved in AR. it left brown yellowish powder. is this RH?

 

[g_axelsson]

after using zinc! black poder is dissolved in AR. it left brown yellowish powder. is this RH?

Don't know, but take a sample of your zinc and dissolve in AR to see if you are getting the same powder. If you are using zinc powder it might be something added to the powder so it doesn't stick together. It's called an anti caking agent.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=51&t=14856&p=149715#p149715

Göran

 

[cuchugold]

... or you could dissolve the ceramic honeycomb, and retrieve near 100% of the powdered metals. Hoke's chapter 16 for clues. Extremely unprofitable, dangerous, poisonous, not recommended, warning, danger, etc, etc. But simple.

edit: ANYTHING involving Fluorine or HF is a pain to deal with. The ideal product would be something safe and simple to deal with, and which byproducts of the reaction would be very cheap to recycle. Some superacid or superbase maybe. I don't have the solutions really, because unless you can also fabricate new catalytic converters and sell them, the PGM markets are basically an inaccessible oligopoly.

 

[goldenpuncture]

thanks göran. i get zinc scrap and melt it. well i will do as you say as i have zinc from same type of scrap and will also try to post the pictures. thanks. if there is a straight way of testing this powder whether its rh or not , then please tell me as i can further test it. it will more educated than testing zinc in hcl!!!