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Poor mans aqua regia solution black

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Poor mans aqua regia solution black

Postby Robonca » May 5th, 2012, 10:02 pm

Hello to all I processed pm's different ways with good results. I did poor mans ar with ammonium nitrate then used urea. Filtered, then put solution in a crock pot and turned on.. Added some water a white percipient formed I then added smb. There was then a layer of white on the bottom brown in the middle. I read somewhere on this forum I could put al in to drop all metals. So I put a few al can tabs in, then I had a reddish percipient on top of the other two. I processed a gold plated watch and some old pentium pros. Are these layers cu1 au and fe? After I kept adding al tabs solution became somewhat clearer.. Should I filter all powders and process.. Thanks this is my first post...

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Re: Poor mans aqua regia solution black

Postby NobleMetalWorks » May 5th, 2012, 10:17 pm

SMB would have dropped the gold along with other metals, then you should wait 24 hours before doing anything else. There was no need to add Al. You could have used Ferrous Sulfate instead of SMB, but both do about the same thing.

At this point I would wait the full 24 hours, then take a picture a post it here for more help. In the meantime...

Did you test with Stannous Chloride for gold/pm in solution before you used SMB to drop gold? Have you tested the solution after your additions of SMB, before the Al?

What have you done up until this point?

Have you read Hoke?

If you are more clear about what you have done up to this point, someone may be able to help you, if you post pictures that would be even better. But if you haven't read Hoke, a lot of the advice people may give you, will not make any sense at all.

At the heart of science is an essential balance between two seemingly contradictory attitudes--an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. -- Carl Sagan

"When I get a little money I buy books; and if any is left I buy food and clothes". Erasmus (1467-1536))

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Re: Poor mans aqua regia solution black

Postby Barren Realms 007 » May 5th, 2012, 10:18 pm

Well guess what, since you added the al tabs and your solution turned clear you probably dropped all your metals out of solution including the base metals you already had in solution.

Best suggestion would be for you to let everything settle and siphon off your solution and be prepared to start over.

This time tho download you a copy of Hoke's book that will teach you about recovery and refining of PM's, put your material away till you have read her book and come back to it with a different outlook on what you are doing to recover your PM's.

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Re: Poor mans aqua regia solution black

Postby Robonca » May 7th, 2012, 9:57 am

here is it.. I just let this sit for 48 hrs. should I filter then reprocess.. how should I process? poor mans ar or something else thanks. I didn't test with stannous, I'm going to make stannous with some tin and HCl.. I think I see silver chloride all so, does it look like big white crystals? I'm also reading hoke, on page 55.. thanks again..
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Re: Poor mans aqua regia solution black

Postby butcher » May 7th, 2012, 12:12 pm

The gold plated watch very well could have added iron and other metals you did not want in solution (it alone would have cemented out the gold, if you had any metals un-dissolved from this process the can be gold plated, but it would not look like gold, copper from ceramic processors, aluminum, you added (we do not want aluminum in solution with gold), all in an aqua regia solution, your powders may or may not be gold in that jar in your picture.

I would not process the plated watch with the processors; in fact it is best to separate different types of materials to process them.

Take a small sample of solution heat it and add a prill of urea (test tube), look for fizzing reaction indicating nitric acid, if fizz add another prill, we wish to remove nitric to be able to test solution, a drop of this solution on a Qtip or filter paper then a drop of your stannous chloride, a violet color indicates gold in solution (here normally I would not recommend using urea, as it can be hard to tell if nitric is gone, but since you already added it to your solution I did), I do not think you have values in solution but you really do not know until your stannous test verifies it.

I would not recommend using ammonium nitrate as the nitrate source, when making your poor mans aqua regia, or other solutions, it can be dangerous, you do not want to make something that could explode, when used with metals, and heat, the sodium nitrate or potassium nitrate is much safer to use as nitrate source.

I also do not recommend using urea to denoxx a solution, there are some people who use it but I believe it just adds other contaminates, and could also form dangerous compounds, using the minimum required amount of nitric and the evaporation method, or Harold's trick the gold button is what I would use.
Your waste solution you will need to treat for waste, put it in a plastic bucket with good lid, read dealing with waste in the safety section.

Decant solution from the powders, heating these powders covered in hydrochloric acid, (I use a corning cassarole dish on a solid hot plate burner), (normally I would say boil, but here if you have iron in the powders which can form iron hydroxides from high heat, basically rust that will not dissolve in acid, keep solution warm, and decant the colored solution into a collection jar (any powders in the bottom of this jar could hold values), the solution can be decanted using a suction bulb or pipette, repeat the hot HCl wash of your powders, till color of solution is not strongly colored with metals, then use hot water washes till clear, decant into same collection jar, let powders settle in collection jar, test solution for values, and treat for waste, the powders in the collection jar should be washed in boiling water, before adding to other powders, then these can be added to the main batch of washed powders.

Here I would take a small grain sample of these washed powders in a test tube, add a couple of drops of HCl and a drop of bleach, heat it, and check color for base metals if very green the main powder will need re-washing. Also then test for gold with your stannous chloride, if all looks good you can start over and refine these powders.

If the powders can then be reprocessed, (HCl and bleach process would be easier than dealing with aqua regia), You will need to refine the powders a couple of times to get rid of the base metals, doing the gold powder washing technique Harold posted in between your refining (read getting gold pure and shinning in the help needed section).

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