Leaching ore with Aqua Regia

[saadat68]

I don't want recovery gold from ore but someone ask me this question. Here many peoples recovery gold from sulfide and oxide ores with aqua regia (here there is no free gold like north america). Of course the amount of gold in those ores is very high (for example 3 or 4 gram in one kilogram of ore) :shock:

 

[butcher]

They should learn better recovery methods.

 

[butcher]

saadat68,
How much do you know about the mining in your area, how the gold was recovered and processed historically, and how it is done today?

Do you know of all of the processes involved with the ore before it sees aqua regia in the mining industry in your area?

I just cannot believe someone is mining a ton of rock of sulfide composition roasting it and attempting to dissolve the gold out of the ton of powdered ore with aqua regia for an ounce of gold.

Maybe for leaching of the other metals involved but not even then I cannot see anyone using aqua regia...

Now if the gold was recovered and concentrated through some other pretreatments and processes first, such as sulfide floatation and concentration of the values, and then we were discussing roasting and leaching those concentrates with aqua regia at these later stages I could understand.

 

[saadat68]

There are some gold mining industry in this area. They use cyanide method. But I speak about native peoples that steal ores from these mines and industries!
Some of them that have more ores, for example minimum 100 kg per day, use smelting method. and many that have less gold for example 5 kg per day, use aqua regia method (I am sure they use aqua regia without flotation and etc).
They grind and roast ores and then leach it in AR. Those ores are cheap or free with 1 to 7 gram in one kg ore! Also energy, acid and labor are cheap too. So I think these parameters make their work be profitable.
One of them asked me can I remove base metals from roasted ores with HCl and Nitric without dissolving gold, and I can't answer to him.

 

[butcher]

If nitric is that cheap that they can just waste it and other acids by consuming it by leaching crushed rock. they may not need to roast the ore.
Nitric or H2O2 can be used to desulfurize the gold compound, similar to roasting it will release a slew of deadly compounds from the rock, the acids can also leach gold along with the many other base metals, making a toxic solution or mess that if they are lucky they may recover some of their stolen gold before they poison everyone around them by their methods of dealing with the waste.

Leaching sulfide ore with aqua regia in anything more than just doing testing on a small scale is just simply a stupid idea. waste of time and money and putting us all at risk from the environmental dangers.
Just like the open burning of tons of electronic scrap polluting the environment for a few pennies of metals.