Precipitate silver in aqua regia ?

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Such small amount's of AgCl are very easy to wash out with ammonia so no need to fuss.
But it seems to be the correct answer for the initial question."Is there a way to precipitate silver in an Aqua Regia solution ?"
Yes there is but in such small quantity's it is technical interesting but impractical for any worth while recovery.
 
I believe Nick is saying he gets paid for the gold content whether it's pure or not. I really don't think he meant to say they paid the same price for 97% as 99%. If you get paid for the gold content, the purity is not a big issue unless the lots are so big there's a hefty handling charge involved.
 
Hi
If we leach silver or silver compounds with AR and then filter residue. How much silver or silver chloride will be in solution ? nothing ?
Can you say in percent for example ?

Thanks
 
saadat68 said:
Hi
If we leach silver or silver compounds with AR and then filter residue. How much silver or silver chloride will be in solution ? nothing ?
Can you say in percent for example ?

Thanks
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This is for dissolving gold that contains silver, like karat gold. Leaching silver or silver compounds may or may not produce the same results and this probably depends on whether the silver is finely divided or not, the temperature, and the specific silver compound. However, when cooled to room temp, I doubt if the numbers will exceed those given below, in any case.

With full strength AR (no added water), about a gram or two per liter at room temperature. With ANY dilution (e.g., when filtering and then rinsing), some of this dissolved AgCl will precipitate. If diluted to 25% AR with 3 parts water, about 98% (maybe more) will precipitate. That is why I always dilute AR 3 to 1 before filtering. Far more effective in eliminating silver from the solution (proven), simpler, and less messy than using ice. As a bonus, the dilution tends to reduce the effect of excess nitric and makes the gold reduction go smoother. Even though I sometimes get a little sloppy and go overboard with my nitric usage, since I started diluting 3:1 I can't remember ever having to treat the standard AR solution in any way for excess nitric (evaporation, sulfamic acid, etc) before dropping the gold with a sulfite. The only exception was when using so-called reverse AR (50% nitric).

I once experimented with all of this, but that was almost 50 years ago. I can't remember the exact numbers, but what I've given above are close.
 
Yes! Try to put salt (NaCl) on your aqua regia with dissolve silver(Ag).

During pouring of salt on aqua regia, white powder will appear and soon will be settle under, that white power is silver collect them. Then cook it.

Best regards,
Jason
 
Maybe it's just me... But, I dont think I would cook AgCl. I would definitely convert it to metallic silver first. Or, at the very least, silver oxide.

Cooking silver chloride will not only poison you, but create losses, and (obviously) dry it out. So when you do decide that the process didn't work as you hoped, converting it will be that much more of a pain to do. It's not impossible, but it will make you resent yourself for making something thats inherently so cheap, so difficult to reclaim.
 
Topher_osAUrus said:
Maybe it's just me... But, I dont think I would cook AgCl. I would definitely convert it to metallic silver first. Or, at the very least, silver oxide.

Cooking silver chloride will not only poison you, but create losses, and (obviously) dry it out. So when you do decide that the process didn't work as you hoped, converting it will be that much more of a pain to do. It's not impossible, but it will make you resent yourself for making something thats inherently so cheap, so difficult to reclaim.
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I took it to mean cooking it in liquid.
 
goldsilverpro said:
I took it to mean cooking it in liquid.
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Hopefully so, maybe tesaygo can give some more detail on what he meant for our friend saadat68. If not for anything else, but to help alleviate some of the questions he will undoubtedly have.
 
To convert silver chloride, stable material boiling at 1550C, to silver you can "cook" it with iron (e.g. nails), taking care for the iron chlorides that evolve
 
If after you have dissolved everything and you're ready to filter. Chill the AR with tapwater ice cubes. Let chill and settle and the silver will have precipitated out to the bottom.
 
tesaygo said:
Yes! Try to put salt (NaCl) on your aqua regia with dissolve silver(Ag).

During pouring of salt on aqua regia, white powder will appear and soon will be settle under, that white power is silver collect them. Then cook it.

Best regards,
Jason
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I'm not sure what is meant by "cooking" the silver chloride mentioned here.

My recommendation would include a number of things.
1. Any time you're going to try something you haven't yet done, like putting salt in your AR, Take a very small sample and try it on that sample first so if something goes awry, you haven't messed up your whole batch.
2. Carefully filter your AR, the silver chloride will not go through a proper filter and that can be one way for you to collect it.
3. look up Lye method of converting your silver chloride. When you have clean silver chloride in a beaker or some other container, add regular household LYE (no additives, just plain lye - sodium hydroxide) and while stirring (safely, you have to decide how and with what equipment you'll be using, eg magnetic stirrer?) and your white silver chloride will convert to black silver oxide. Then using some sort of sugar (Karo syrup, dilute it a little to thin it or use as is) and the silver oxide will convert to metallic silver. It will appear dark but have a shiny gray appearance. The sugar will carmalize and be very brown also so don't let that fool you. Dilute/wash that, let settle, repeat several times until clean and you can melt that powder. It can be very pure but that depends on your technique. Ive done it a number of times and it works. Those reactions create ALOT of heat and steam so use caution and proper beakers/containers/equipment.

Good luck.
 
Topher_osAUrus said:
Maybe it's just me... But, I dont think I would cook AgCl.

Boiling your aqua regia with gold in it (AgCl) WILL cause significant losses. I know. I've done it. It boils it right out of the beaker.
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Harold_V said:
Sue said:
Noxx said:
Hello,
Is there a way to precipitate silver in an Aqua Regia solution ? Either before or after gold.
Thanks
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The scientific answer is yes, there is always a method to attempt this. The difficulty comes in justifying costs versus results. What is your goal?

a man named Sue
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Nonsense!!!

One can not have silver in solution in AR. Any silver present as a nitrate will immediately precipitate as chloride when AR is introduced. That's why gold and silver as so easily parted.


Harold
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How did you put it? NONSENSE!! Lol

Actually, I've had some silver in the bottom of the AR like you said, but that was usually left there because of passivation. But depending on how much silver is present, if you chill the AR with tapwater ice cubes, you will have any silver in solution precipitate out. I certainly have. I don't know why that happens, because when you dissolve silver in nitric acid, one way to precipitate the silver is to add HCl and it will precipitate it out as silver chloride. That IS one way I do it (bleach does the same thing and can be cheaper). So I don't know why, but that has happened to me.
 
ARMCO said:
Topher_osAUrus said:
Maybe it's just me... But, I dont think I would cook AgCl.

Boiling your aqua regia with gold in it (AgCl) WILL cause significant losses. I know. I've done it. It boils it right out of the beaker.
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You can boil AR without having "significant losses" quite easily.

Edit for context.
 
Are you speaking theoretically or from actual experience? I ask this respectfully. I HAVE had the experience of significant losses and have also been told by others that can happen, actually told WILL happen if you boil AR and I have never done it again. Everything I've looked up also strongly discourages boiling in favor of evaporation due to this occurrence as well.

As I said, maybe your experience has been different, but mine has been as stated above.

Also, if you would be willing, could you check out my "Too much SMB" post. I would sincerely like to hear your thoughts.

This is my first time on a refining forum

thank you
 
justinhcase said:
As even silver chloride(AgCl) is soluble in H2O I find I get a little AgCl carried over in my AR.
Even on second run Au after reduction I get a small amount of white precipitate once I re-hydrate the reduction.
For some reason a concentrated Gold Chloride solution keep's this small amount of impurity's in solution until I add a bit more water.
Which seems counter intuitive as the rest of the low solubility impurity's drop out with out the re-hydration.
So Technically you can precipitate silver out of AR but as AgCl and only in very small amount's .
Or is that to fine a line to be considered a precipitation,it is more of a release of trace impurity's rather than a true compound precipitation.
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Ah!, I should have read a little more before I posted. You just explained why I have gotten the results I described. Thank you
 
Ive boiled AR and didnt suffer great losses as well.(when I had to, dissolving platinum)
I simply use a watch glass, and a piece of fiberglass insulation balled up to put in the lip of the beaker, which soaks up any of the values that try to eek their way out of the vessel.

Not having the reaction vessel more than 1/3 full helps a great deal as well.

I dont usually heat it that strongly, but I always use the fiberglass plug, as even the bubbling from a regular dissolution of gold likes to find its way out of the beaker lip just as much.

------

And, it may or may not be "technically" a precipitation, but the AgCl when in the gold chloride solution is held in as AgCl2, when diluted it becomes turbid and slowly falls to the bottom of the beaker.
This "flaky condition" AgCl is oddly enough "soluble in pure or acidified water, though, curiously enough, either silver nitrate or alkaline chloride will reprecipitate it from this solution. (This explains the so called 'neutral point' in the Gay Lussac method of estimating silver volumetrically)" -[The Metallurgy of Silver - Collins]

It may be important to know (for some), that "If the gold is precipitated out via SO2 when this silver is in solution, it will form silver sulfite (AgSO3) [Loewen, pg 124]

Okay, Im done quoting books now, I just thought those two excerpts fit well in this thread... Back to your regularly scheduled programming
 
Topher_osAUrus said:
Ive boiled AR and didnt suffer great losses as well.(when I had to, dissolving platinum)
I simply use a watch glass, and a piece of fiberglass insulation balled up to put in the lip of the beaker, which soaks up any of the values that try to eek their way out of the vessel.

Not having the reaction vessel more than 1/3 full helps a great deal as well.

I dont usually heat it that strongly, but I always use the fiberglass plug, as even the bubbling from a regular dissolution of gold likes to find its way out of the beaker lip just as much.

------

And, it may or may not be "technically" a precipitation, but the AgCl when in the gold chloride solution is held in as AgCl2, when diluted it becomes turbid and slowly falls to the bottom of the beaker.
This "flaky condition" AgCl is oddly enough "soluble in pure or acidified water, though, curiously enough, either silver nitrate or alkaline chloride will reprecipitate it from this solution. (This explains the so called 'neutral point' in the Gay Lussac method of estimating silver volumetrically)" -[The Metallurgy of Silver - Collins]

It may be important to know (for some), that "If the gold is precipitated out via SO2 when this silver is in solution, it will form silver sulfite (AgSO3) [Loewen, pg 124]

Okay, Im done quoting books now, I just thought those two excerpts fit well in this thread... Back to your regularly scheduled programming
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Actually, i really appreciate it. After a couple years of trial and error, YouTube, and some books I figured I should get involved in a forum. There is so much I don't know. I spend an inordinate amount of time, and have had success, but I'm still fighting certain problems. So, thanks again.
 
ARMCO said:
Are you speaking theoretically or from actual experience? I ask this respectfully. I HAVE had the experience of significant losses and have also been told by others that can happen, actually told WILL happen if you boil AR and I have never done it again. Everything I've looked up also strongly discourages boiling in favor of evaporation due to this occurrence as well.
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It's from experience not just from theory. 8)
 
anachronism said:
ARMCO said:
Are you speaking theoretically or from actual experience? I ask this respectfully. I HAVE had the experience of significant losses and have also been told by others that can happen, actually told WILL happen if you boil AR and I have never done it again. Everything I've looked up also strongly discourages boiling in favor of evaporation due to this occurrence as well.
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It's from experience not just from theory. 8)
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:cool:
 

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