Help! HElp! Help! Expert needed

[jnixon]

5 years of chemistry 25 years ago need help. Using HCl +H2O2 Au was recovered from finger trimmings.

I had a nice orange solution indicating ag was dissolved and should now be AuCl3. Using SMB I dropped ag, so I thought. Must have been some copper as well. I have 3 different pecips. after drying to long in coffee pot (washed 3 times in HCl and 3 times in De-ionized H2O) I have a shiny black powder, a light grey powder and and a dark brown/orange powder. I thought I did something wrong and put it all back in HCl+H2O2 where it turned orange again and I got the same result except one odd thing. The light grey powder/mudd will not dissolve again in the HCl=H2O2.


Also, can the leftover chems be reused? what would the final equation look like after the SMB be?

Please help me identify the precips.

Also, the SMB was first added to De-ionized H2O than pured into the AuCl3. Is this wrong? Pretty sure I have no salts left over, I cleaned it all pretty well.

Last question, when putting whole boards in HCl+H2O2, how do I precipitate out each desired metal and in the most efficient order?

Thanks, I know I asked a lot, hope it is challenging enough. Oh and I documented everything and am happy to send you the word document with pics.





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[Ian_B]

Ag is Silver
Au is Gold

If you used Hydrochloric acid and Hydrogen Peroxide on trimmed computer fingers it should turn a greenish hue because of the dissolved copper

the gold foils shouldn't dissolve in AP (Acid Peroxide) although minute amounts of gold can dissolve in AP the foils should just separate from the boards and be free. You should then of taken the empty clean peices of finger trimmings and cleaned them off with water to make sure the foils were left in the solution. Then you filter the solution so that you are left with the foils in the filter. then wash and process foils whatever way you decide.

or did you make a solution of Aqua Regia HCl+HNO3 ?

edited to include bolded

 

[jnixon]

Yes, it was green when I first dissolved the fingers. Yes, I was left with foils. Look at the attachment in the original post. It will show you the process.

After I washed the foil, I used the HCL+H2O2 and it did in fact dissolve the foils and turn orange. It took about a day and a half for all the foils to dissolve. The precipitate I have left from tthat one is black and shinny.

The other two unidentified precipitates are from boards not clipped (wholde boards).

 

[jnixon]

Oh, I did use stannouse chloride to test. No idea what the dark brown is or grey is.

 

[Ian_B]

Ag doesn't dissolve in HCl+H2O2 and turn into AuCl3

Why are you making a how to document if you don't even know what the proper steps are?doesn't it seems a bit dangerous to make a how to when you don't know what the end products are? and by products?

 

[jnixon]

The how to is just for my documentation. Not as an educational tool for someone else. And yes, the gold did dissolve, however i don't know the balanced equation.

 

[Ian_B]

The how to is just for my documentation. Not as an educational tool for someone else. And yes, the gold did dissolve, however i don't know the balanced equation.

Ag is Silver
Au is Gold

Ag cannot dissolve in HCl and turn into AuCl3

Silver cannot dissolve in Hydrochloric acid and turn into Auric Chloride/Gold Chloride

 

[jnixon]

You are correct, i am dyslexic and used ag instead of au. Please forgive and read knowing this. Thanks

 

[Ian_B]

"Clip fingers from boards/ram and/or drop entire board with high quantity gold foil/plating in HCl + H2O2 solution" I hope you didn't drop that board that contains capacitors into the acid peroxide solution, I also noticed in the second picture of you procedure that to the right of your bucket handle their is a piece of board that has what looks like a blue wire attached GIGO garbage in Garbage out.

if you were to depopulate the computer boards before you process them with the acid peroxide then you would be ensuring that you pregnant solution would contain a minimal amount of waste metals that you would have to eliminate later.

the foils that you are left with after the first acid peroxide mix would be better off being washed and then dissolved in HCl-Cl and then dropped with SMB

the absolute best idea however would be to buy the DVD that lasersteve has created that goes step by step through this process and I guarantee you that at the end of it if you follow his steps to the T you will be left with a higher quality end product then the method that you are using from you document that you have posted.

 

[jnixon]

Here, sometimes less is more. tell me if this is correct.

HCl + H2O2 + Ag=

Ag + 2HCl + H2O2 -----> 2AgCl + 2H2O

Is this correct?

If so, what is this?

Na2S2O5 + 2AgCl→ 2 NaCl + 2 SO2 please balance this

 

[jnixon]

"Clip fingers from boards/ram and/or drop entire board with high quantity gold foil/plating in HCl + H2O2 solution" I hope you didn't drop that board that contains capacitors into the acid peroxide solution, I also noticed in the second picture of you procedure that to the right of your bucket handle their is a piece of board that has what looks like a blue wire attached GIGO garbage in Garbage out.

if you were to depopulate the computer boards before you process them with the acid peroxide then you would be ensuring that you pregnant solution would contain a minimal amount of waste metals that you would have to eliminate later.

the foils that you are left with after the first acid peroxide mix would be better off being washed and then dissolved in HCl-Cl and then dropped with SMB

the absolute best idea however would be to buy the DVD that lasersteve has created that goes step by step through this process and I guarantee you that at the end of it if you follow his steps to the T you will be left with a higher quality end product then the method that you are using from you document that you have posted.

Thanks Ian, I guess this dogs gotta go back to the pound for retraining.

 

[goldsilverpro]

I don't think you did that bad. You shouldn't have run the entire boards through the acid mix and you used way too much SMB - ideally, it takes an oz of SMB to ppt an oz of gold. If you added too much H2O2, it could have dissolved some gold, but this would have immediately cemented onto the undissolved base metals as a black/brown powder. This could be hung up on the boards.

You're almost there. Just read more and try to understand WHY. The thing I appreciate is that you obviously studied and made a fairly good attempt before asking questions. We get a lot of lazy, annoying, irritating people that want us to hold their hand from the very start. You didn't do that.

Welcome to the forum.

Chris

 

[jnixon]

I don't think you did that bad. You shouldn't have run the entire boards through the acid mix and you used way too much SMB - ideally, it takes an oz of SMB to ppt an oz of gold. If you added too much H2O2, it could have dissolved some gold, but this would have immediately cemented onto the undissolved base metals as a black/brown powder. This could be hung up on the boards.

You're almost there. Just read more and try to understand WHY. The thing I appreciate is that you obviously studied and made a fairly good attempt before asking questions. We get a lot of lazy, annoying, irritating people that want us to hold their hand from the very start. You didn't do that.

Welcome to the forum.

Chris

Chris, thank you for your diplomatic reply. This is the kind of reply that makes me want to hold on tight to child like curiosity and read more, your education and experience and others.

I ran two separate trials, one with just fingers and one with whole boards. The question is...what is the black powder, gray powder and dark brown powder. The black powder, as you may have indicated, is base metals precipitated with gold on the? Is this why it is orange when I dissolve it again? The grey powder odes nothing in piranha and the dark brown dissolves easily and returns to the same when precipitated.
Is it correct to just re-dissolve it all and drop just the gold, or is it too late for that and another process to be used to recover the gold. I estimate it should be about 15/16 grams or more 1/2 a troy oz.

Thanks again. You lack arrogance and are informative and supportive. I just don't want to do anything dangerous or lose the product.