Dissolving copper ingots(containing pd and au)in ar

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arthur kierski

Well-known member
Joined
Feb 10, 2008
Messages
1,090
Location
são paulo---brazil
Up to now,i made agua regia (3 or4 hcl + 1volume of hno3)---now i have copper ingots weighting 1kilo(with 4grans of pd and1gram of au). I would be very glad if some members ,could calculate the quantityes of Hcl and Hno3 in volume,that i must use to dissolve these 1kilo ingots----as an example,i use 4litres of nitric acid to dissolve 1kilo of copper ingots-----thanks in advance ,for replies -----------------------------------------------------------------Arthur Kierski
 
If your material was in shot form would it not aid in digestion? Small shot seems to dissolve quicker for me than large bars.
 
yes,i will make shots of the copper ingots--it is the same way as is done with silver? i am also thinking of laminating,it also makes thin sheets----But still,would like to have an idea of how much Ar---thanks for your reply
 
This a copy of some notes I've saved:
NOTE: When substituting nitrates for nitric acid in Poorman's AR here are some handy numbers:

1. When used to dissolve gold powders use 4 mL of 31% HCl per gram of gold plus:

1.343 g NaNO3 (sodium nitrate) per gram of gold to be dissolved.
or
1.597 g KNO3 (potassium nitrate) per gram of gold to be dissolved.

2. When used to dissolve copper based scrap 4 mL of 31% HCl per gram of copper plus:

5.35 g NaNO3 per gram of copper to be dissolved.
or
6.36 g KNO3 per gram of copper to be dissolved.

3. When using NaNO3 be sure to include 1.5 mL of water in the reaction per gram of NaNO3 used. When using KNO3 be sure to include 4 mL of water per gram of KNO3 used.
*ALSO, SEE NOTE @ BOTTOM OF PAGE*
These numbers are the theoretical values. The actual required amount will vary with reaction conditions and reflux of the vapors. With good temperature control (just below boiling) and proper reflux (watch glass or condenser) the actual required amount of nitrate (or nitric) can be reduced.

The best mileage from the nitrate can be obtained when it is added in small increments during the course of the reaction. Let each addition fully react (all tiny bubbles cease and red vapor in condenser clears) before adding the next dose. Start with very small doses to avoid boil over’s. As the reaction nears completion, (all of the target metal is dissolved), add only very small amounts of the nitrate. Steve
If you are using nitric,
It takes about 129.2 ml of nitric acid to dissolve 1 troy ounce of copper.
And GSP once posted that 1 gallon of 34% HCl will dissolve about 3 pounds of copper.
I hope these notes help.
Phil
 
Why are you dissolving that in ar? Did I read it wrong? Copper with 1% Pd and 1/4% Au?

Dissolve in nitric, filter Au, cement Pd.


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Even more though, that alloy is begging to be done in copper cell.


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Thanks Philddreamer---your notes are very valuable ---it helps me with my own notes----Snoman, i will use ar,because the quantities of acids,is much less them using nitric acid nitric alone--- I will not use a copper cell because it takes a long time in the process----i have over 500kilos of this wire----thanks for all your coments-----but if you have a number of how much Ar is needed to dissolve 1kilo of copper,in shots or laminated, i would be very glad-----if nitric is easier then ar,i might eventually use it------there are wires richer in pms---rh with gold,pd with silver-----thanks again
 
I have used a wet plank of wood in iced water to pour copper shot and it went well, but I have never poured any where near the weight you have. I was mostly curious to know how you you would do it as you have more knowledge of refining than I do.

I also enjoy your posts for help, as they are always something over my head and I learn quite a lot from many of them.
 
I would try it on a small batch first. I think you will face difficulty precipitating the Pd from solution.
 
Shark,thanks in reading my posts---- i always made shots with silver--here in Brazil silver is sold as shots--here we do the folowing(with silver):the silver is fused and trhown into a bucket with water,and some alcohol, the alchool makes the shots brilliant and does not oxidize the silver shots--i hope it works with copper----as the shots are trown into the bucket,one has to stir the water with a wood stick-----Snoman,i precipitate the palladium using dmg----is quick and very good-----I already made a test with a small batch ,and worked well--- thanks again for the questions
 
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