Dropping gold from AP and AR

[viktor1984]

(1) Ok here is my problem. i dissolved gold random stuff from ram and cpus. after i removed most base metals. i dissolved it Via poor mans AR method and after all gold was dissolved i used up all my urea to nutralize the acid and it looked like it wasnt fizzing anymore. so then i dissolved some SMB with water and added it to the solution and it fizzed and i did get alot of brown powder on the bottom of the bucket.
but when i test the solution if there is anymore gold that is in the solution and the test comes out positive for gold. and when i add more SMB it still showes gold after testing and its been like this for 2 days now. How do i get the gold drop out of solution all the way??? i heated the solution overnight still positive any sugges.?

 

[lazersteve]

What color is the swab test?

A common false positive with stannous chloride on the swab after the gold is precipitated from solutions.

Check my website documents section for Sulfurous Acid document for chemical explanation. In essence you made sulfurous acid with the excess SO2, adding stannous chloride (tin in acid solution) you made hyposulfurous acid. Zinc is used in the referenced document, but any soluble metal above hydrogen in the activity series chart will produce the same effect.

During this reaction the tin forms sodium and hydrogen sulfides (rotten egg smell -- very deadly!!!) which is a strong reducing agent which pushes all metals out of solution as dark colored (brown, gray, or light black) powders (metal sulfide stain).

Steve

 

[viktor1984]

The test color is black

 

[lazersteve]

The test color is black

Do you have a photo?

Steve

 

[viktor1984]

the first 2 pictures are before and after tests.
the other pictures are of the solution.

 

[lazersteve]

The swab looks brown to me. Test for Pd using DMG, if negative then false it's a positive. Gold will be purple. When the stannous is dropped onto the swab do you smell a rotten egg (hydrogen sulfide) odor? Don't inhale directly onto the swab, but try to waft a slight wiff of the swab to your nose. Do this in outdoor where there is plenty of fresh are flowing as hydrogen sulfide is deadly in fairly low concentrations.

What is the sediment in the bottom of the solution?

Steve

 

[viktor1984]

sediment in the bottom of the solution is what dropped when i used SMB.
i do not have any DMG
and when i put a drop on the swab it does smell like nasty rotten eggs.
what do i do now?

 

[lazersteve]

Don't add any more SMB.

Pour off the solution without the sediment as it may contain gold.

Rinse the sediment several times with water and post a photo of your results.

Steve

 

[Barren Realms 007]

Don't add any more SMB.

Pour off the solution without the sediment as it may contain gold.

Rinse the sediment several times with water and post a photo of your results.

Steve

Steve I'm not so sure he has gotten all of the nitric out of the solution. Might need to boil this down some.

 

[viktor1984]

i heated it in a crockpot for a whole night on high.
im rinsing the sediment with water now and it looks like a very fine heavy powder on buttom.

i also rinse it with hcl after rinsing it with water right?
and if its gold it will remain on bottom correct?

 

[Barren Realms 007]

i heated it in a crockpot for a whole night on high.
im rinsing the sediment with water now and it looks like a very fine heavy powder on buttom.

i also rinse it with hcl after rinsing it with water right?
and if its gold it will remain on bottom correct?

You heated the solution or just the cleaned powder in a clean solution? How much volume of liquid did you evaporate off?

 

[viktor1984]

i heated the whole solution not the clean wated with powder.
it evaporated about half of it out. well 2 out of 5 quarts

 

[goldsilverpro]

Heating doesn't buy anything when eliminating nitric. Evaporation is what's important. If nitric is the problem, it looks like you have 3 more quarts to evaporate.

 

[Barren Realms 007]

If it were me I would do a small sample with SMB and see what it does, but that is me. Follow what Steve tells you to the letter.

 

[Barren Realms 007]

Heating doesn't buy anything when eliminating nitric. Evaporation is what's important. If nitric is the problem, it looks like you have 3 more quarts to evaporate.

Is it ok to do it with the heat adjusted to just above nitrics evap point or should it be done at a boiling temp?

 

[lazersteve]

Steve I'm not so sure he has gotten all of the nitric out of the solution. Might need to boil this down some.

Barren,

If he had excess nitric in solution he would have reported that the solution foams and emits brown gas when the extra SMB was added. Also the fact the he has a solid in the bottom that is not fizzing or redissolving is a good indication he has eliminated any free nitric also.

Vic,

Here's a link on how to proceed with the powder:

Washing Gold Powder

Steve

 

[Barren Realms 007]

Steve I'm not so sure he has gotten all of the nitric out of the solution. Might need to boil this down some.

Barren,

If he had excess nitric in solution he would have reported that the solution foams and emits brown gas when the extras SMB was added. Also the fact the he has a solid in the bottom that is not fizzing or redissolving is a good indication he has eliminated any free nitric also.

Vic,

Here's a link on how to proceed with the powder:

Washing Gold Powder

Steve

Thanks Steve, I had a brain fart there for a second. Where's that dunce hat at. :roll: