Ceramic CPU processing

[FrugalRefiner]

If you still have all your waste solutions it would be a good idea to place a copper bar on them. You will surprised at how much silver you get from them. Its usually close to the same weight as the gold.

Thanks again!

Are you sure about that? I know a small amount of silver can be in solution in strong AR, but it should precipitate when you dilute your solution prior to precipitating your gold. I have a hard time believing he would find that 21 grams had remained in solution, but I could be wrong.

Dave

 

[tek4g63]

Really should be careful how I word things.

Yes you are correct most of the silver would have already been filtered out as silver chloride. Some may still be in solution. The lower quality ceramics some times have notable amounts of silver. I'm probably should not have said nearly as much silver as gold. Just thought that I'd give him a tip on recovering as much values as possible.

What I do is:

Collect the filters with the white/ grey powder in them. Dry and incinerate when I have enough. Then put the powder and ash in a jar for later processing. This jar is labeled silver chloride dirty. Don't have enough collected to bother converting back to metal yet. Then I cement any other values, dry the powders and incinerate. Then when I have enough of those powders I will digest with dilute nitric and filter then recover that silver.

So you are right, I have no way to know the exact amount of silver, I just know that it is there. I will not make this mistake again. Thank you for keeping the data accurate.

 

[FrugalRefiner]

Wow, I really hate to do this again, but I don't think you should let your silver chloride dry out. If I recall correctly, it causes it to create a crystaline structure that will make conversion more difficult when you try to process it back to metallic silver. It would be better to keep your AgCl wet until you're ready to process it.

Dave

 

[tek4g63]

Wow, I really hate to do this again, but I don't think you should let your silver chloride dry out. If I recall correctly, it causes it to create a crystaline structure that will make conversion more difficult when you try to process it back to metallic silver. It would be better to keep your AgCl wet until you're ready to process it.

Dave

Thank you for that advice. Hopefully this will keep others from making the same mistakes. I'll start keeping them wet from now on.

By wet do you mean with water, or something else? Please clarify.

 

[FrugalRefiner]

I believe water should be fine. If I'm wrong I'm sure someone will correct me. :lol:

Dave

 

[denim]

Hey tek4g63- thanks for the compliment. I believe FrugalRefiner might be correct with the silver chloride thing being as I did use ice cubes and 3 times volume dilution. I did check the five gallon bucket of smb solutions and found no traces of gold, but I did not ever think to check for silver. I've had my head wrapped around gold only but maybe in the future.... I do actually keep the silver chloride in a jar with- you guessed it- H20. I believe I read in Hoke that one should keep his silver nitrate in HCL, but silver chloride will do fine in water. As you can see by the picture below I really believe in testing with stannous.

Best regards,

Dennis

 

[g_axelsson]

... I believe I read in Hoke that one should keep his silver nitrate in HCL, but silver chloride will do fine in water.

I guess that you were going to write silver chloride, not nitrate.

Göran

 

[denim]

Thanks for the correction Goran. I had wrongly interpreted what Hoke was saying on pages 48-49. She was talking about using HCL instead of salt to precipitate silver chloride from a nitric acid solution. Since I was not using nitric, and had already precipitated silver chloride using dilution this was a mute point. As you can see I have plenty to learn.

Dennis

 

[Geo]

Harold has taught me that gold and silver can not stay in the same solution together except under certain situations such as cyanide leach. AR will hold a tiny bit of silver in solution but its relative to the temperature.the colder the solution, the less silver it can hold.dilution will drop a certain amount at ambient temps.as the solution is chilled,more will drop.it is a certainty that if silver is in the mix when you dissolve the metals, the silver will report with the gold to the final process. thats why you have to follow the washes and rinses with hcl and ammonium hydroxide to reduce the silver to trace amounts.

 

[denim]

Thanks Geo. Actually I did refine as per Heralds method of hcl wash, ammonia wash, then another hcl wash. I did this for each of the two refinings. The first hcl wash was the only one that showed any color change, after that the rest were perfectly clear. I tested the first hcl wash with stannous and it showed some (very little) gold. It went in the stock pot.

Dennis