Aqua Regia method with 12-13% Ag _inquart_

[giahylxag]

Hello everyone and happy new year!
Unfortunately I couldn't conduct any test last month.
I am going to make my first test next week.
My friend and I had a hot debate about the optimal process for my gold. He is pro chemistry, but I don't, really I don't know much about chemistry.
Given the gold alloy weight 1kg, with 60%Au and 13%Ag. We are debating 2 options
A: To go directly into the inquarting process. I don't want to say how because everyone here explained throroughly.
B: As my friend proposed. Go with AR, get gold around 90-99%, but lose some gold in the Au/AgCl. Then gather that and make an Au-Ag alloy, then inquart it to retrieve Au.
Both process will recover Ag by electrolysis.
____________________
What is your comment?

 

[Yggdrasil]

Hello everyone and happy new year!
Unfortunately I couldn't conduct any test last month.
I am going to make my first test next week.
My friend and I had a hot debate about the optimal process for my gold. He is pro chemistry, but I don't, really I don't know much about chemistry.
Given the gold alloy weight 1kg, with 60%Au and 13%Ag. We are debating 2 options
A: To go directly into the inquarting process. I don't want to say how because everyone here explained throroughly.
B: As my friend proposed. Go with AR, get gold around 90-99%, but lose some gold in the Au/AgCl. Then gather that and make an Au-Ag alloy, then inquart it to retrieve Au.
Both process will recover Ag by electrolysis.
____________________
What is your comment?

For B you either need to convert the AgCl to Silver or smelt it with flux Bi Carbonate I think.
And the Gold are not in loss just a bit delayed.

 

[4metals]

Silver Chloride is like rust, it forms quickly and coats the surface. Much like rust it slows down further corrosion by inhibiting the ability of the chemistry to reach what you are dissolving. More Silver in the alloy amplifies this process.

It is a really tough choice because 12-13% is high. If you choose the aqua regia method, you will benefit greatly by slowly tumbling the reaction to mechanically remove the Silver Chloride coating. And only trying it will tell you if it is working effectively enough.

The inquartation method is almost fool proof, and you will probably need it to completely dissolve the remnants on the insolubles if you use aqua regia first.

If it were me, I would inquart first because it removes all of the Silver and cleans up the alloy to 99+% Gold quickly. And copper cementation will give you a nice Silver metal for a small Silver cell. And you skip dealing with Silver Chloride processing completely.

I am a big fan of keeping all of the values from a single lot together to make accounting easier, not chasing a few percent of gold all over the shop for days. For security in a refinery that is a good thing, and by inquarting you will know quickly that your recovery meets expectations. That cuts down on theft.

 

[4metals]

He is pro chemistry, but I don't, really I don't know much about chemistry.

The less you know about chemistry, the better inquartation looks!

 

[giahylxag]

For B you either need to convert the AgCl to Silver or smelt it with flux Bi Carbonate I think.
And the Gold are not in loss just a bit delayed.

Well that is my worst fear when thinking about refining gold. At the end of the day when I gather all the stuff and add to calculation then some gold is lost and I don't know why. I just made a lost.

 

[giahylxag]

The less you know about chemistry, the better inquartation looks!

That's how my friend told me *laugh*

 

[4metals]

smelt it with flux Bi Carbonate I think.

Soda ash, carbon powder, and a borax cap if you go the melt route.

But the resultant silver metal will have gold in it, maybe 1 or 2%, and you won't see that back until you clean up the anode slimes. That can be weeks to months!

 

[giahylxag]

If it were me, I would inquart first because it removes all of the Silver and cleans up the alloy to 99+% Gold quickly.

It seems getting gold to 99+% even to 99.95+% consistently at a home refining is not hard at all. But it seem really hard to get 99.99% Why? Is this the limitation of AR and one can only get 99.99% by electrolysis?

 

[Yggdrasil]

It seems getting gold to 99+% even to 99.95+% consistently at a home refining is not hard at all. But it seem really hard to get 99.99% Why? Is this the limitation of AR and one can only get 99.99% by electrolysis?

No, but there are impurities in the water, acids and precipitants.

 

[giahylxag]

No, but there are impurities in the water, acids and precipitants.

Distilled water, tech grade acid, and SO2 as recipitant is good?
Most of the refined bars in my market come up with silver (0.005%) as impurity

 

[Yggdrasil]

Distilled water, tech grade acid, and SO2 as recipitant is good?
Most of the refined bars in my market come up with silver (0.005%) as impurity

Should be good, but needs plenty washing after precipitation.
There are procedures from Harold_V to get 59 by these means.
Search the forum.

 

[Shark]

Filtering plays a large part in purity as well. Poor technique or some make do filter papers can allow tiny amounts of various impurities through, and it will show up in your gold when melting. Even something as simple as a dirty torch or burner in the furnace can bring about small impurities.

 

[Yggdrasil]

Distilled water, tech grade acid, and SO2 as recipitant is good?
Most of the refined bars in my market come up with silver (0.005%) as impurity

Another question is why to do it?
It won't pay much better than 99.5 and its cost are way higher.

 

[giahylxag]

Another question is why to do it?
It won't pay much better than 99.5 and its cost are way higher.

Given the market price here they pay 0.5% more from 9995 to 9999. 9999 can make coins and bars. Quality under that can make jewelry

 

[Shark]

Another question is why to do it?
It won't pay much better than 99.5 and its cost are way higher.

In my case, just to know if I can do it. I want the best I can produce, to satisfy myself. If the buyers like, it is even better.

 

[giahylxag]

In my case, just to know if I can do it. I want the best I can produce, to satisfy myself. If the buyers like, it is even better.

Me too.
I just want to reach the limit

 

[giahylxag]

Filtering plays a large part in purity as well. Poor technique or some make do filter papers can allow tiny amounts of various impurities through, and it will show up in your gold when melting. Even something as simple as a dirty torch or burner in the furnace can bring about small impurities.

Most of the time I see there is silver impurity in bars that I got. As low as 0.003%.

 

[Yggdrasil]

Most of the time I see there is silver impurity in bars that I got. As low as 0.003%.

Filtering the solution diluted with Ice cold water will remove most of the Silver Chloride.
Washes the powders with Ammonia will too even though I seem to recollect there were reasons not to do it.

 

[giahylxag]

Filtering the solution diluted with Ice cold water will remove most of the Silver Chloride.
Washes the powders with Ammonia will too even though I seem to recollect there were reasons not to do it.

Found the thread here
https://goldrefiningforum.com/threads/final-ammonia-water-wash-necessary.2064/

 

[FrugalRefiner]

Here are a couple of posts/threads that may help.

Lou's Washing Procedure

Method for Ultra High Purity Gold

Dave