Not dissolving in ar.

[Rival metals]

Good day all,
After dropping solution with smb I managed to get a fair amount of brown persipitant from 3 batches. , dried it off, washed in boiling water 3 times , cooked it in Hcl, and it was still brown and the same amount was left with all of the treatments. I was getting really excited at this stage as I made plenty of mistakes during the process, and I found myself rectifying more than actually processing gold. The powder was placed in with AR .I let it boil continuously for about 2 hours putting in nitric 2ml at a time . I left the solution overnight. This morning I woke up only to find my AR did not dissolve any of the powder, stannous showed no indication of gold in solution, and it turned pure white. What kind of salt does not dissolve in AR???
Regards
Terence

 

[butcher]

I have no clue what you are working on or what material you have, but there can be many things that will not dissolve in aqua regia.

Metals like lead, silver, and mercury are insoluble as chlorides.
Iron salts can look like gold in solution, Iron salts or iron oxides can also be insoluble in acids...

Without knowing what you are doing or have done it is hard to say what you have.

Why are you boiling aqua regia?

 

[Rival metals]

Hi Bucher,

I have been trying to get gold out of Gold pins and gold plated pins for some time now. Making heaps af mistakes along the way. Finaly I decided to cement out all the metals with iron and start over.
So from the cemented metals (which I assume would have been gold, lead, silver, copper, tin, and what ever else there might have been in it) I started again . Bit by bit dissolving it in AR. I ended up with about 20 liters of solution. Then I used copper to sement out the metals, left it stand for about a week. Finally I had about 1.5 liters of solution in which my final product would have been left. I used smb to get the gold out and ended up with about 180ml of brown powder. So that's the story...
Terence.

 

[Rival metals]

Sorry Bucher to awnser your last question, this was part of the washing prosess, and wanted to make sure the gold I had was pure. That's why I placed the powder back in AR. as part of a second refinement.

 

[butcher]

Terence,
My guess, and I am just guessing, from your last post the brown powder is most likely loaded with iron oxides (basically iron rust) and other base metal salts.

From your description of your attempt to recover gold, I would say you are just chasing your tail with no clue, and yourself getting nowhere faster than you would like to.

You are using an awful lot of acids, making an awfully big mess of toxic waste to deal with, and you cannot tell where the gold is now and where it is not.

You can try asking a million questions, and get a million different answers and still be lost.
You can read about it, it sounds easy, just go this or that way, it sure sounds easy to find the way with just a little direction and some answers, but the problem rears its head again because, without some understanding, you soon find yourself lost again on the journey upon entering the dark woods.

Why are you using nitric or aqua regia, and why are you boiling or cooking acids?

Sorry I do not have any answers, only a suggestion, deal with this toxic solution, put away the chemicals, and study more before proceeding further, starting with Hoke's book and the getting acquainted experiments, and studying the recovery processes you are planning on using well before beginning, Begin working with acids again, only after gaining more understanding and working only in small batches in small experiments until you gain some experience and understanding...

 

[Rival metals]

Thank you Butcher.

 

[butcher]

Terence,
Along with your study of Hoke's and the practicing of the experiments she suggests to gain an understanding of the reactions of different metals and acids, you can continue to use these same types of small experiments on your own to gain a better understanding of the other processes your learning about or doing with your gold recovery projects.

It may also be easier to learn and gain experience, by starting your learning processes with simple materials and simple processes, using materials like karat gold, sterling silver, or better yet memory fingers to learn the basics on.

Memory finger is an easy material to learn to recover gold from and to learn the basic principles, you do not need nitric or aqua regia, you gain an understanding without the problems you would encounter with many of the other electronic scrap or the problems with using nitric or aqua regia, or from problems, you would encounter from troublesome metals like tin...

Work in small experiments, only after you study each process thoroughly, gaining a good understanding of how to prepare the scrap, test the scrap, mechanically prep it, and then recover the gold, and the processes of refining the gold...

Work on your skills of testing for gold and other metals in solution, do many small experiments to get acquainted with how the test is performed why it works, and why it may not work or show a positive result even if there is gold in the solution...

Basically start at the beginning by learning the basics, gain a good understanding of the basic principles, before trying to run, we may do better by learning to walk well, then running becomes easier, we learn to avoid problems, use the basic understanding to recognize and be able to solve more complicated problems as they arise, we build on our understanding then we are more able to move on to more complicated materials using what we learn as we go to learn more complicated processes...

Try setting up small experiments on your own, with things you wish to gain more understanding of or are learning about. So just for kicks, try a few drops of aqua regia in a test tube add some red rust, (which can look like dissolved gold in solution) does it all dissolve? Does it not dissolve? how do you test to see if gold or iron is in solution? Can the rust form a white powder, or can the iron color the solution much like gold does? Now add some black iron rust and repeat you're testing does it react the same similar or different if so why? Now How do iron metal filings react?
...