Newbie help with salt for gold extraction.

[glaucodobrasil]

[stt]Hey there,
I processed about 175 complete pcs in a cyanide gold stripper I found.
At the end, the liquid was very between yellow/gold/orange, almost a salsicha water color.
The instructions says to add a amount of |sodium hydroxide (100g) each 5l when the solution gets saturated.
I saw instructions here in the forum to keep the pH between 11.3~12 before adding the zinc powder. But my solution have a pH of 12.6.
Should I decrease the pH using small amounts of HCl before adding the zinc, or it is good to go?

Actually the instructions that came with the salt was not good as I wish. They said to add around 50g of zinc powder for each 5l of solution (which can hold around 125g of gold). Do you think this zinc amount is correct for that amount of gold to recover?
Tks![/stt]

Don't do that! Never! Don't kill yourself, don't be an idiot.

 

[Justincase]

Please hold your horses until you have consulted some good authority and studied the reaction properly.
I can not believe you have started a cyanide recovery with so little understanding of the process.
One set of instructions are not going to be enough to stop you killing your self with such activity's.
Hope you understand how earnest I am.I have never even thought of using cyanide yet.

 

[glaucodobrasil]

Please hold your horses until you have consulted some good authority and studied the reaction properly.
I can not believe you have started a cyanide recovery with so little understanding of the process.
One set of instructions are not going to be enough to stop you killing your self with such activity's.
Hope you understand how earnest I am.I have never even thought of using cyanide yet.

I've been helped a little by a member who know the process very well. Honestly, I don't know if it is a cyanide solution or it is another name. I could give you the PDF with the documentation, but it all in Portuguese.
But I do follow all the instructions: use gloves, glasses, mask when needed, do acids outside, don't drink it, don't taste it, don't smell it, don't throw it away.

 

[arisas]

hello i don't know about cyanide method but i know that its more safe and more certain the use of AP method, Nitric Acid method and AR method, i have about 500 pcs and around 25 boxes of boards (motherboards,hard drives,DVD Drives,Floppy Drives, etc)all this time i use these methods and things go as they should be , why to risk you precious metals when you can do it the simple way.

 

[glaucodobrasil]

hello i don't know about cyanide method but i know that its more safe and more certain the use of AP method, Nitric Acid method and AR method, i have about 500 pcs and around 25 boxes of boards (motherboards,hard drives,DVD Drives,Floppy Drives, etc)all this time i use these methods and things go as they should be , why to risk you precious metals when you can do it the simple way.

Well, it is just my opinion. Sorry if I'm wrong, I don't wanna discuss. But I think that the way you go is not that simple and safe. I did a lot of these steps. Lets see:
1-) Separate pins, fingers and ICs, using a sharp tool;
2-) Separate thousands of sharp pins from their cases using pliers;
3-) Cut fingers using sharp scissors or guillotines that can cut your fingers too;
4-) Process fingers using strong HCl for four days inside a bucket with an air pump, outside or using an expansive fume hood;
5-) Process pins using hot sulfuric acid, a charger, and a sheet of copper;
6-) Process plastic processors using a torch;
7-) Process ceramic processors using hot HCl and nitric acid;
Process IC Chips using furnace or torch, then hot nitric acid like partnor101 taught us;
9-) Finally, more hot HCl and nitric acid;
10-) After all that work that you take weeks and weeks, you will have to follow a lot of other dangerous steps to get silver and will let some gold behind in hard places to get, like the memory cases. It is a miracle to get alive after all this dangerous work.

or
[stt]1-) Separate ICs using a sharp tool;
2-) Dump everything with gold in a dangerous solution and let drain;
3-) Sodium hydroxide, zinc;
4-) Hot nitric;
5-) Hot HCl and nitric acid;
6-) Process IC Chips using furnace or torch, then hot nitric acid like partnor101 taught us;
The steps 1-5 you do in a single day even if you have 100 PCs. Less acids, less sharp things, less fire, and to process silver is very similar.

For sure I'm not a chemist, but I can't imagine why the cyanide process is so more dangerous than the other one. You have to follow all the rules from the lab in any case, you will not die only because you are next to cyanide:
1-) Always use individual protection equipment;
2-) Don't touch it, don't smell it, don't drink it, wash your hands;
3-) Keep everything closed and sealed in properly containers if not in use;
4-) Never throw nothing in the sink unless you really know what you are doing;
5-) Storage everything until you have enough to pay a company to dispose, or get more informations in your city water department.[/stt]

Don't do that! Don't be stupid! Don't kill yourself!

 

[FrugalRefiner]

This forum has taught me that there are many ways to skin the cat. Every method has its place, depending on an individual's circumstances. Every method has hazards.

The best advice is to educate yourself THOROUGHLY in whatever method(s) you choose before you start.

Dave

 

[butcher]

Devil is in the small details, details you may not be aware of, educating yourself in the process before attempting anything, can help protect you from dangers in small details you may not be aware of.

Little details like letting the pH of a cyanide solution become acidic can be a deadly mistake.

 

[glaucodobrasil]

Devil is in the small details, details you may not be aware of, educating yourself in the process before attempting anything, can help protect you from dangers in small details you may not be aware of.

Little details like letting the pH of a cyanide solution become acidic can be a deadly mistake.

That's it. And I'm not using correctly what I learned in this forum. I should separate a small portion and try an experiment using some little HCl and then use the zinc powder. If decants, works. That's what I should do, right?

 

[butcher]

Adding any acid or HCl to adjust the pH can become very dangerous, one of the devils in the details you need to understand before using cyanide.
Experimenting with chemicals and producing a deadly gas is not the way to learn, sometimes we can learn the hard way, but if you do not live through the experiment, I do not think you gain much of an education for your future, experimenting with chemicals can become your last experiment if handled wrong.

 

[glaucodobrasil]

Adding any acid or HCl to adjust the pH can become very dangerous, one of the devils in the details you need to understand before using cyanide.

I have 1,6l of sausage's juice to process, I'm already with the devil.

 

[Justincase]

Adding any acid or HCl to adjust the pH can become very dangerous, one of the devils in the details you need to understand before using cyanide.

I have 1,6l of sausage's juice to process, I'm already with the devil.

Put away until you have studied further.
You have a potential cyanide bomb,adding any acid may gas a considerable aria.

 

[glaucodobrasil]

Put away until you have studied further.
You have a potential cyanide bomb,adding any acid may gas a considerable aria.

Alright... Is all well sealed in a well ventilated room. Let's check Hoke...

 

[Justincase]

http://www.infomine.com/publications/docs/Botz1999.pdf

 

[butcher]

4 Au + 8 NaCN + O2 + 2H2O → 4 Na[Au(CN)2] + 4 NaOH
In the reaction above gold + sodium cyanide + oxygen + water rect to produce a gold cyanide complex and sodium hydroxide, keeping the pH on the basic side of the scale, the high pH also helps to keep the gold in solution, normally with the leach keeping the pH high enough to keep the gold in solution is the problem, and keeping the pH high as not to produce a deadly hydrogen cyanide gas is also a problem.

I do not think that the pH being 12.6 would be a problem when using zinc to cement the gold from solution. The zinc would still displace metals from solution.

My guess here on how much zinc would depend on many factors, how much metals are in solution,temperature... and maybe the pH of the solution may use a little more zinc, but that would be safer than acidifying the solution.

I do not use cyanide although I have studied it some, but not enough to use it myself, or to be a reliable source of information, so take what I have to say with that grain of salt and educate yourself in the subject.

 

[glaucodobrasil]

4 Au + 8 NaCN + O2 + 2H2O → 4 Na[Au(CN)2] + 4 NaOH
In the reaction above gold + sodium cyanide + oxygen + water rect to produce a gold cyanide complex and sodium hydroxide, keeping the pH on the basic side of the scale, the high pH also helps to keep the gold in solution, normally with the leach keeping the pH high enough to keep the gold in solution is the problem, and keeping the pH high as not to produce a deadly hydrogen cyanide gas is also a problem.

I do not think that the pH being 12.6 would be a problem when using zinc to cement the gold from solution. The zinc would still displace metals from solution.

My guess here on how much zinc would depend on many factors, how much metals are in solution,temperature... and maybe the pH of the solution may use a little more zinc, but that would be safer than acidifying the solution.

I do not use cyanide although I have studied it some, but not enough to use it myself, or to be a reliable source of information, so take what I have to say with that grain of salt and educate yourself in the subject.

Alright butcher, very straightforward. I was scared enough with that acidifying thing. I will not do that and try some zinc as a test with a small sample.

 

[butcher]

The reaction of gold + sodium cyanide + oxygen + water
4 Au + 8 NaCN + O2 + 2H2O → 4 Na[Au(CN)2] + 4 NaOH
sodium aurocyanide and sodium hydroxide formed

Using zinc to displace the gold (it is important remove oxygen before attempting to cement the gold, the oxygen can keep gold in solution, by re-dissolving it back into the solution).

Displacing gold from solution using zinc metal shavings.
2Au(CN) + Zn = 2Au + Zn(CN)4-2

Zn + 4NaCN + 2H2O → Na2[Zn(CN)4] + 2NaOH + H2
Zinc reacts with excess sodium cyanide and water to produce sodium tetracyanozincate(II), sodium hydroxide and hydrogen. The reaction takes place in a boiling solution (I am unsure if the reaction itself would produce enough heat).

During leaching and to keep the gold in solution and to prevent the creation of toxic hydrogen cyanide during processing, slaked lime (calcium hydroxide) is normally added to the extracting solution to ensure that the acidity during cyanidation is maintained over pH 10.5 - strongly alkali.To help keep gold in solution and to prevent a deadly hydrogen cyanide HCN gas from forming.

It would be a good idea to keep a supply of sodium thiosulfate on hand to destroy the cyanide if something goes wrong in the processes.

Sodium thiosulfate, which reacts with cyanide:
Na2S2O3 + NaCN → Na2SO3 + NaSCN
Forming sodium sulfate and sodium thiocyanate
This is also the reactions used in the treatment of cyanide poisoning.

 

[glaucodobrasil]

The reaction of gold + sodium cyanide + oxygen + water
4 Au + 8 NaCN + O2 + 2H2O → 4 Na[Au(CN)2] + 4 NaOH
sodium aurocyanide and sodium hydroxide formed

Using zinc to displace the gold (it is important remove oxygen before attempting to cement the gold, the oxygen can keep gold in solution, by re-dissolving it back into the solution).

Displacing gold from solution using zinc metal shavings.
2Au(CN) + Zn = 2Au + Zn(CN)4-2

Zn + 4NaCN + 2H2O → Na2[Zn(CN)4] + 2NaOH + H2
Zinc reacts with excess sodium cyanide and water to produce sodium tetracyanozincate(II), sodium hydroxide and hydrogen. The reaction takes place in a boiling solution (I am unsure if the reaction itself would produce enough heat).

During leaching and to keep the gold in solution and to prevent the creation of toxic hydrogen cyanide during processing, slaked lime (calcium hydroxide) is normally added to the extracting solution to ensure that the acidity during cyanidation is maintained over pH 10.5 - strongly alkali.To help keep gold in solution and to prevent a deadly hydrogen cyanide HCN gas from forming.

It would be a good idea to keep a supply of sodium thiosulfate on hand to destroy the cyanide if something goes wrong in the processes.

Sodium thiosulfate, which reacts with cyanide:
Na2S2O3 + NaCN → Na2SO3 + NaSCN
Forming sodium sulfate and sodium thiocyanate
This is also the reactions used in the treatment of cyanide poisoning.

Ok, this is great. I think I will read this response for the next week or so before trying anything. The other member who are helping me almost had a heart attack when I said if is a good idea to reduce the pH of the solution using HCl. I think he will not return to help me again. Before, he told me to keep a zinc bar in the solution in case I do not do the zinc cementation immediately.

Very tks butcher!

 

[glaucodobrasil]

The reaction of gold + sodium cyanide + oxygen + water
4 Au + 8 NaCN + O2 + 2H2O → 4 Na[Au(CN)2] + 4 NaOH.
2Au(CN) + Zn = 2Au + Zn(CN)4-2
Zn + 4NaCN + 2H2O → Na2[Zn(CN)4] + 2NaOH + H2

maintained over pH 10.5 - strongly alkali.To help keep gold in solution and to prevent a deadly hydrogen cyanide HCN gas from forming.

It would be a good idea to keep a supply of sodium thiosulfate on hand to destroy the cyanide if something goes wrong in the processes.

Sodium thiosulfate, which reacts with cyanide:
Na2S2O3 + NaCN → Na2SO3 + NaSCN
Forming sodium sulfate and sodium thiocyanate
This is also the reactions used in the treatment of cyanide poisoning.

Alright, yesterday I put some zinc powder in a sample solution and nothing happens. I will filter everything again, and later add some little more fresh solution to try turn things back to 4 Na[Au(CN)2] + 4 NaOH. At least my pH is very stable over 12.8. So, no deadly gas yet.

 

[jeneje]

At least my pH is very stable over 12.8. So, no deadly gas yet.

Why would you DO any experiments and/or TESTS, without knowing exactly what the outcome will be with this type of chemical process. Life must not mean much too you.

Good luck,
Ken

 

[glaucodobrasil]

At least my pH is very stable over 12.8. So, no deadly gas yet.

Why would you DO any experiments and/or TESTS, without knowing exactly what the outcome will be with this type of chemical process. Life must not mean much too you.

Good luck,
Ken

As I said, a member from this forum is helping me, so I felt confident to try it.