Reduction of gold from a mixed solution

Gold Refining Forum

Help Support Gold Refining Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
And after a long time I understood why my powder almost all dissolved in HCl. If I were to reduce the powder, I would decant it and immediately start washing it in HCl instead of washing it well several times from all the salts and the solution it was in.
 
It is about copper - Copper was soluble in all concentrations in distilled water pH 5.5. At higher pH values, the amount of soluble copper was a function of both pH and total copper concentration, with a maximum of 4 mg/l soluble copper at pH 6.5 and a maximum of 1.3 mg/l soluble copper at pH 7.4. Copper should be rinsed with water.
 
add alkali, NaOH or CaCO3 or NaCO3 or bicarbonate

Does pH affect gold?
It can be interpreted that the temperature and pH should be above 55 °C, respectively 11.5, in order to achieve high gold extraction, in the studied range of leaching conditions.
So why in the world do you want to elevate the pH?
That will make the SMB nonfunctional and you will drop all metals as Hydroxides
 
So why in the world do you want to elevate the pH?
That will make the SMB nonfunctional and you will drop all metals as Hydroxides
Do you measure the pH and add SMB of the specified pH or until it foams?
Does FeSO4 also have such an effect on the solution, or is it necessary to raise the pH for reduction with it?
 
Do you measure the pH and add SMB of the specified pH or until it foams?
Does FeSO4 also have such an effect on the solution, or is it necessary to raise the pH for reduction with it?
Please answer my question, why do you want to elevate the pH?
Where did you get this procedure?
 
There are translation issues here,
so I try to get a better image on what is going on by asking one or two questions at the time.
 
It is about copper - Copper was soluble in all concentrations in distilled water pH 5.5. At higher pH values, the amount of soluble copper was a function of both pH and total copper concentration, with a maximum of 4 mg/l soluble copper at pH 6.5 and a maximum of 1.3 mg/l soluble copper at pH 7.4. Copper should be rinsed with water.
After reading again, I'm wondering...
Are you trying to get rid of the Copper before dropping the Gold?
 
Please answer my question, why do you want to elevate the pH?
Where did you get this procedure?
I was advised that the use of gold is greater as in the case of washing between hydrochloric and hydrochloric acid, to destroy the HCl by leaching so as not to get a gold nugget and the gold dissolves again
 
Now I have the powder boiled in dilute HCl and washed three times. Is it better to add lye to neutralize the HCl or fry. Frying creates unpleasant gases. Then expose to the action of HNO3 because I know it has palladium.
 
I was advised that the use of gold is greater as in the case of washing between hydrochloric and hydrochloric acid, to destroy the HCl by leaching so as not to get a gold nugget and the gold dissolves again
This sentence do not make sense.

Do you mean that the Gold redissolves in HCl/Cyanuric acid?
That is not because of the HCl, that is because of the Cyanauric acid still produces Cl- ions that makes the Gold redissolve.

You can not destroy HCl nor HNO3 with boiling, for Nitric we can use Sulfamic acid.
No such luck for HCl.
The only way is to evaporate and roast it.

Where did you find this advice?
 
It seems to me that you prefer to find out how others work than to give advice on what and how is best. I want to get the best result. I've been working on my knees for too long surrounded by experts.:confused:
We need to understand what you have been doing and what you have.
You give way to little information.

Unless we know what you have done in detail we can just give you a recipe for bread, it is just as useful.

What about giving us the information we need in order to advice you.
You are the one in need of advice.
 
This sentence do not make sense.

Do you mean that the Gold redissolves in HCl/Cyanuric acid?
That is not because of the HCl, that is because of the Cyanauric acid still produces Cl- ions that makes the Gold redissolve.

You can not destroy HCl nor HNO3 with boiling, for Nitric we can use Sulfamic acid.
No such luck for HCl.
The only way is to evaporate and roast it.

Where did you find this advice?
obviously in the wrong place, thanks for the instructions
 
Now I have the powder boiled in dilute HCl and washed three times. Is it better to add lye to neutralize the HCl or fry. Frying creates unpleasant gases. Then expose to the action of HNO3 because I know it has palladium.
No use for NaOH need to neutralize.
Just wash well in water and the powder is ready.
How do you know there is Pd in it?
If you are going to add Nitric, you need to roast it first to decompose the HCl.
 
No use for NaOH need to neutralize.
Just wash well in water and the powder is ready.
How do you know there is Pd in it?
If you are going to add Nitric, you need to roast it first to decompose the HCl.
I know because I have extracted several times individually from the solution. platinum, palladium, gold at the end.
During melting, there was too much copper in it, so I gave up everything for a long time.
 
Back
Top