Failed! POOR'S MAN NITRIC ACID

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mythen10

Well-known member
Joined
Jun 25, 2022
Messages
259
Hi , yesterday after I see a couple of movies on YouTube about Poor's man nitric acid i decide to try this method.
I start like in a movie with gold plated fingers , I was added about 520 gr(this contain minimum 2.5 gr of pure gold). I put the fingers with sulfuric acid ,water and potassium nitrate on stove and is start the reaction like in the YouTube clip, after 10 minutes the foils from fingers start coming down floating all around in solution (I was so happy), after another 20 minute the solution become saturated and I filter the foils and replace the solution with a fresh one, checking the saturated solution with SNCL show me a positive test for gold this mean the poor's man nitric acid dissolve some foils. After 10 minutes the replaced solution of poor man nitric acid it dissolve all foils from fingers (I was so sad).
CONCLUSION: POOR MAN NITRIC ACID DISSOLVE THE GOLD.
The PROBLEM: I combined that two solution and I was added urea followed by addition of SMB dissolved in water and the solution was directly changed the colour to black and the gold it was start to precipitate, I collect the gold and I test the solution with SNCL for gold and the test was possitve, I try to add more SMB a excess of SMB AND PMB I was added and after several hours on the bottom of beacker it was a slug of gold with SMB ant PMB wich I successfully refine with HCl and hydrogen peroxide.
I recover in total about 1.6 gr of gold(I must recover minimum 2.5 gr of gold from 520 gr of fingers) and the problem was the waste solution still contain gold who don't want to precipitate and I put that solution in to a bucket to try to precipitate with copper.
IN CONCLUSION POOR MAN NITRIC ACID WILL DISSOLVE THE GOLD AND MAKE VERY HARDER TO ISOLETE THE GOLD FROM SOLUTION.
(after this I try with gold plated fingers an same result the gold go in solution)
 
The only thought I have is perhaps your water if from the tap had some chlorides in it hence allowing some gold to dissolve.
 
The only thought I have is perhaps your water if from the tap had some chlorides in it hence allowing some gold to dissolve.
and after I read on internet the sulfuric acid will dissolve the gold, probably this is the problem sulfuric acid dissolve the gold
 
The only thought I have is perhaps your water if from the tap had some chlorides in it hence allowing some gold to dissolve.
they say on internet the sulfuric acid when is in combination with nitric acid will dissolve the gold, this mean the reaction between nitrate salt and sulfuric acid gone wrong it start to make nitric acid wich meat the sulfuric acid from solution
 
they say on internet the sulfuric acid when is in combination with nitric acid will dissolve the gold, this mean the reaction between nitrate salt and sulfuric acid gone wrong it start to make nitric acid wich meat the sulfuric acid from solution
Sulfuric do not dissolve Gold, unless it is used in an electrolytic cell. And even then it is not the Sulfuric acid, but the Persulfuric acid created by the voltage very close to the anode.
So if it actually dissolves Gold it is likely that your Nitrates or Sulfuric is contaminated with Chloride of some kind.
 
Sulfuric do not dissolve Gold, unless it is used in an electrolytic cell. And even then it is not the Sulfuric acid, but the Persulfuric acid created by the voltage very close to the anode.
So if it actually dissolves Gold it is likely that your Nitrates or Sulfuric is contaminated with Chloride of some kind.
https://www.911metallurgist.com/blo...ept,when these are present in a silver alloy. this is the site they say sulfuric acid when meet nitric acid will dissolve the gold this mean THA POORS MAN NITRIC ACID is not the best choice because the nitric acid formed will react with interacted sulfuric acid and will dissolve the gold
 

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Sulfuric do not dissolve Gold, unless it is used in an electrolytic cell. And even then it is not the Sulfuric acid, but the Persulfuric acid created by the voltage very close to the anode.
So if it actually dissolves Gold it is likely that your Nitrates or Sulfuric is contaminated with Chloride of some kind.
this is very good for dissolving silver
 
https://www.911metallurgist.com/blo...ept,when these are present in a silver alloy. this is the site they say sulfuric acid when meet nitric acid will dissolve the gold this mean THA POORS MAN NITRIC ACID is not the best choice because the nitric acid formed will react with interacted sulfuric acid and will dissolve the gold
This is new to me, any one else?

Usually when people use poormans they use only nitrates and water.
Sulfuric comes in to play when they try to make Nitric from Nitrates.
And then either use the freezing or distillation method the get cleanish Nitric.
 
This is new to me, any one else?

Usually when people use poormans they use only nitrates and water.
Sulfuric comes in to play when they try to make Nitric from Nitrates.
And then either use the freezing or distillation method the get cleanish Nitric.
Are on YouTube couple videos this is the video and me I repeat to get the foils from 520 gr fingers and I recover initial 1.6 gr and 2 hours ago I recover another 0.3 gr in total now I have 1.9 gr 24 k from 520 gr fingers wich contain minimum 2.5 gr 24k gold , but the waste solution still contain gold the sncl is positive and I put in my waste solution bucket and I wil cement out with copper.
 
This is new to me, any one else?

Usually when people use poormans they use only nitrates and water.
Sulfuric comes in to play when they try to make Nitric from Nitrates.
And then either use the freezing or distillation method the get cleanish Nitric.
is not so bad in final the result but was time when the result it was very bad , and if you repeat this procedure from that video with poor man nitric acid you will end with foils dissolved in solution( BUT ME I USE POTASSIUM NITRATE NOT SODIUM NITRATE the author say the potassium nitrate will work)
BUT I BELIEVE THIS IS BEST CHOICE FOR DESSOLVING SILVER FOR PURIFICATION
 
I have used this a good bit and never had a problem. What color was the stannous test? Geo explains really well in the video.
 
Try diluting a few drops of it and test it again. See if the color changes.
the waste solution has gold , after first drop I add more SMB and PMB and is precipitate more gold but not all from waste solution
 
What is the oral (original) volume of the solution now combined?

This is my first thoughts. Evaporate (not boil) off 20-25 percent of the solution and try again. Use only SMB as I have never used the other. Mix 4-5 grams of smb with 50ml hot water dissolve all of the smb. Heat the solution to the same temperature as the smb solution. Then add the hot smb to the hot solution.
Edit: keep it hot for a while to see if the solution will drop. It is usually fairly quick though.

Or, and this may be the better way, cement it out with copper. This would be the way to go many times when a reaction goes wrong and the user does not have the chemistry background to work it out on paper (I am one of those without the right background). It uses fewer chemicals which can cause more problems later on Cementation is a very handy tool to understand and use.
 
Last edited:
What is the oral (original) volume of the solution now combined?

This is my first thoughts. Evaporate (not boil) off 20-25 percent of the solution and try again. Use only SMB as I have never used the other. Mix 4-5 grams of smb with 50ml hot water dissolve all of the smb. Heat the solution to the same temperature as the smb solution. Then add the hot smb to the hot solution.
Edit: keep it hot for a while to see if the solution will drop. It is usually fairly quick though.

Or, and this may be the better way, cement it out with copper. This would be the way to go many times when a reaction goes wrong and the user does not have the chemistry background to work it out on paper (I am one of those without the right background). It uses fewer chemicals which can cause more problems later on Cementation is a very handy tool to understand and use.
I put all solution in to waste bucket and I will process letter with copper I have there more than half gram
 
Hi , yesterday after I see a couple of movies on YouTube about Poor's man nitric acid i decide to try this method.
I start like in a movie with gold plated fingers , I was added about 520 gr(this contain minimum 2.5 gr of pure gold). I put the fingers with sulfuric acid ,water and potassium nitrate on stove and is start the reaction like in the YouTube clip, after 10 minutes the foils from fingers start coming down floating all around in solution (I was so happy), after another 20 minute the solution become saturated and I filter the foils and replace the solution with a fresh one, checking the saturated solution with SNCL show me a positive test for gold this mean the poor's man nitric acid dissolve some foils. After 10 minutes the replaced solution of poor man nitric acid it dissolve all foils from fingers (I was so sad).
CONCLUSION: POOR MAN NITRIC ACID DISSOLVE THE GOLD.
The PROBLEM: I combined that two solution and I was added urea followed by addition of SMB dissolved in water and the solution was directly changed the colour to black and the gold it was start to precipitate, I collect the gold and I test the solution with SNCL for gold and the test was possitve, I try to add more SMB a excess of SMB AND PMB I was added and after several hours on the bottom of beacker it was a slug of gold with SMB ant PMB wich I successfully refine with HCl and hydrogen peroxide.
I recover in total about 1.6 gr of gold(I must recover minimum 2.5 gr of gold from 520 gr of fingers) and the problem was the waste solution still contain gold who don't want to precipitate and I put that solution in to a bucket to try to precipitate with copper.
IN CONCLUSION POOR MAN NITRIC ACID WILL DISSOLVE THE GOLD AND MAKE VERY HARDER TO ISOLETE THE GOLD FROM SOLUTION.
(after this I try with gold plated fingers an same result the gold go in solution)
How do you know so exactly that your fingers contain more than 5g/kg gold ? Did you analyzed them ? Because it is fairly common, that fingers can yield around 2g/kg if they are new. I have experience with all kinds of fingers (RAM, PC card, new, older, Soviet-era etc.) and yields fluctuate quite a bit. I had batches of old fingers that gave me around 6g/kg, but these were no means comparable to modern PC stuff. Average for newer types for me is around 2-3,5g/kg.

Problem could hide in used salts and acid. You can use the purest demineralized water existing, but if you use tech grade sulfuric acid and tech grade nitrate, there is no surprise that chlorides could be present. It is sufficient to have just few decimals of % chloride content in acid or nitrate (I assume contamined nitrate) to solubilize some gold.

And if it happened (gold dissolved in solution), it would be nearly impossible to do it standard way with urea/sulfamic and SMB. Vast portion of salts in the solution are nitrates - for SMB to work, you need acidic pH. Any common acid like sulfuric acid will liberate some free nitric, which will start to re-dissolve the gold. And killing that quantity of nitric acid with sulfamic acid would be fairly wasteful and inefficient.

Only things that came to my mind is to adjust the pH to just slightly acidic and cement the values on copper. But I never done this personally in this situation. Or use the formate reduction method (it run also with high nitrate concentrations).
 
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