Help me about gold-copper cyanide process.

[tesaygo]

As Deano says, there are different types of copper - gold ores and there is no one universal treatment that works well with all of them. If the ore is oxidized, then that will be harder (minerals like Azurite, malachite, chrysocolla, etc.). The only thing I could suggest is a good acid pre-leach to capture the oxidized copper, but he says he has already tried that and it didn't work. I dont know if Tesaygo really understands the chemistry on this, and that is a major problem. Perhaps the problem could be solved, but not knowing all I can say is it is not a simple 1,2,3 and your done process. All sorts of other factors come into play, the size the material is crushed to, any other metal contaminants, how well it was leached, what was used to raise the pH before cyanide was added, how the pH is controlled during cyanide leaching, etc. Mixing acids and cyanide is deadly.
You dont float oxidized copper ores, you float to capture sulfides. In an unoxidized ore you capture all the sulfides (normally mostly a mixure of pyrite and chalcopyrite in many copper ores) and smelt them, separating out the gold, silver and other metals in the copper refining phase after smelting. This may not be of much use to tesaygo even if what he has is unoxidized sulfide ore unless he has a copper smelter nearby that will take concentrates on a custom basis.
In any case, its not a super easy thing to do. There is a reason why no one is looking at the copper-gold ore - the extraction is difficult. I know of a decent deposit here in Nevada of oxidized copper-gold ore and it sits unworked because its too expensive to work it if you need to do a double leach with acid first then cyanide.

Thank you sir Reno,
Sir Deano give me an advise to pre leach in acid the copper-gold ore first, using H2SO4 maintaning a pH level of 1-2, then after acid treatment to remove copper, wash the ore with water to remove all acid left on ore, then adjust the pH for cyanidation process.

By the way what you mean about "You dont float oxidized copper ores, you float to capture sulfides. In an unoxidized ore you capture all the sulfides" are you refering on floatation?
Sir Reano do you have any idea or suggestion for treatment of copper-gold ore, any other process. I only know how to process using cyanidation.

Thanks alot

 

[Mr.c]

Interesting post Mr. C

May I asked some questions:

1. why are you adding hydrogen peroxide in your pre treat solution?

2. are you using vat leaching method?


Thanks Mr. C

Sorry about the late reply. Been busy with work.

To answer your first question, what Iggy said is right. The idea is to convert the sulfides to sulphur or sulphates. Theoretically h202 aid in removing sulfide metals and there are some papers available for that process which i can't recall.

For the second question, yes. I'm using vat leaching method.

As for the OP: what Dean might have told you could be the same process as what I'm doing. Maybe do some small scale leaching (eg. 5kg grounded ore) with different ratios of acid pre treatment to find out which works for you. As Reno said, this acid pretreatment doesn't work with oxidized minerals so keep that in mind.

Just as a reference, currently my head ore seems to increasing in Cu content and have to use about 17kg/ton of nitric acid 68% concentrate.

 

[tesaygo]

Interesting post Mr. C

May I asked some questions:

1. why are you adding hydrogen peroxide in your pre treat solution?

2. are you using vat leaching method?


Thanks Mr. C

Sorry about the late reply. Been busy with work.

To answer your first question, what Iggy said is right. The idea is to convert the sulfides to sulphur or sulphates. Theoretically h202 aid in removing sulfide metals and there are some papers available for that process which i can't recall.

For the second question, yes. I'm using vat leaching method.

As for the OP: what Dean might have told you could be the same process as what I'm doing. Maybe do some small scale leaching (eg. 5kg grounded ore) with different ratios of acid pre treatment to find out which works for you. As Reno said, this acid pretreatment doesn't work with oxidized minerals so keep that in mind.

Just as a reference, currently my head ore seems to increasing in Cu content and have to use about 17kg/ton of nitric acid 68% concentrate.

Hello Mr. C
Do you use nitric acid to pretreatment your gold-copper ore as you mention here? What do you think is the best to use H2SO4 or nitric acid, i know that nitric is more expensive than h2so4, but nitric dissolve alot of none valuable metal but also dissolve Silver, unlike h2so4 dissolve selected minerals.
By the way, can you illustrate how do you operate your VAT leaching, i like to know more what else i need to improve and try which is better way to maximize the extraction of gold. Lets help each other.

 

[Iggy-poo]

Interesting post Mr. C

May I asked some questions:

1. why are you adding hydrogen peroxide in your pre treat solution?

2. are you using vat leaching method?


Thanks Mr. C

Sorry about the late reply. Been busy with work.

To answer your first question, what Iggy said is right. The idea is to convert the sulfides to sulphur or sulphates. Theoretically h202 aid in removing sulfide metals and there are some papers available for that process which i can't recall.

For the second question, yes. I'm using vat leaching method.

As for the OP: what Dean might have told you could be the same process as what I'm doing. Maybe do some small scale leaching (eg. 5kg grounded ore) with different ratios of acid pre treatment to find out which works for you. As Reno said, this acid pretreatment doesn't work with oxidized minerals so keep that in mind.

Just as a reference, currently my head ore seems to increasing in Cu content and have to use about 17kg/ton of nitric acid 68% concentrate.

Hello Mr. C
Do you use nitric acid to pretreatment your gold-copper ore as you mention here? What do you think is the best to use H2SO4 or nitric acid, i know that nitric is more expensive than h2so4, but nitric dissolve alot of none valuable metal but also dissolve Silver, unlike h2so4 dissolve selected minerals.
By the way, can you illustrate how do you operate your VAT leaching, i like to know more what else i need to improve and try which is better way to maximize the extraction of gold. Lets help each other.

Some thoughts about the use of Nitric Acid Leach:

The main thing is that it is illegal here because miners used it in the past and cause severe long-term damage to the environment.
Just because it's legal to discharge untreated waste doesn't mean you should. If you can't make a decent living by properly treating your waste, you should find another line of work.
Nitric Acid will also dissolve elements like Palladium, which is a potent carcinogen. People drinking the water downstream will suffer the consequences.
Neutralizing Sulfuric Acid leach and recovering the Copper and other metals should more than pay for the cost of treatment and release mostly harmless Sodium Sulfate.
Neutralizing Nitrate leach will release Nitrates into the environment and make it more difficult to recover the Copper.
Be a good citizen and study the consequences of your actions.

 

[tesaygo]

Some thoughts about the use of Nitric Acid Leach:

The main thing is that it is illegal here because miners used it in the past and cause severe long-term damage to the environment.
Just because it's legal to discharge untreated waste doesn't mean you should. If you can't make a decent living by properly treating your waste, you should find another line of work.
Nitric Acid will also dissolve elements like Palladium, which is a potent carcinogen. People drinking the water downstream will suffer the consequences.
Neutralizing Sulfuric Acid leach and recovering the Copper and other metals should more than pay for the cost of treatment and release mostly harmless Sodium Sulfate.
Neutralizing Nitrate leach will release Nitrates into the environment and make it more difficult to recover the Copper.
Be a good citizen and study the consequences of your actions.

Hello Iggy,
I agree that improper disposal of acid such as nitric and sulfuric really can harm people and our environment, most local miner here in our country doing that, due to lack of knowledge on proper disposal. Not only in disposal but also lack in knowledge in processing or recovering precious metals. Its really hard to educate them. very hard.

But i am aware of proper disposal of acid but i dont dispose my acid instead we re-use and re-use and re-use.
Does anyone here know if there is a solid or powder form of sulfuric acid? I really hard to transport a liquid form of sulfuric acid. And nitric acid just asking.
Thanks Iggy

 

[Iggy-poo]

Hi,
You can use Sodium Acid Sulfate (NaHSO4). It's like partially neutralized Sulfuric Acid, but in a powder or pellet form. Folks who carry pool supplies usually carry it. In pools,it's used to lower the pH. I use it often and it works well.
If you set up an electrolytic recovery cell, it would strip the Copper and rejuvenate your Sulfuric acid, which could be recirculated.
If you don't have electricity, a couple of Solar Panels could be used instead.
No need to use a pump to recirculate, just use an aquarium pump to inject air into your return line. Like they do with an aquarium. it will carry the rejuvenated acid and aerate it at the same time.

 

[Aeon13]

Sorry about the late reply. Been busy with work.

To answer your first question, what Iggy said is right. The idea is to convert the sulfides to sulphur or sulphates. Theoretically h202 aid in removing sulfide metals and there are some papers available for that process which i can't recall.

For the second question, yes. I'm using vat leaching method.

As for the OP: what Dean might have told you could be the same process as what I'm doing. Maybe do some small scale leaching (eg. 5kg grounded ore) with different ratios of acid pre treatment to find out which works for you. As Reno said, this acid pretreatment doesn't work with oxidized minerals so keep that in mind.

Just as a reference, currently my head ore seems to increasing in Cu content and have to use about 17kg/ton of nitric acid 68% concentrate.

Thanks for the answer Mr. C.Appreciated.


I get the feeling that we are using almost the same methods of leaching gold. You are using vat leaching

which is what the majority of people use here. And yeah the government is not strict at all in terms of

chemical disposal. It's good we have this forum for us to know the proper way of dealing with wastes.


I will just ask some questions about your methods for me to compare and learn new things that you are

doing there which maybe is better since we are in an almost the same situation.

1. Are you using zinc dust to precipitate your gold?

2. Are you doing your assays yourself?

3. Are you using Stannous Chloride to test your cyanide solution for possible gold left?

I don't have access for assays as of the moment that is why I am not sure what other elements are present

in the ores here. I hope to find soon.

Thanks Mr. C!


For the OP.

I agree with Tesaygo when he says that many miners are really hard to educate. Specially if these miners

are older than the one teaching. They think that their experiences are all they need. Plus the government

are not regulating them. The rivers are the waste dumps. So sad.