Trouble with copper in Auric Chloride

[masonwebb]

Hey guys so I have tried to do some small practice batches of HCL+Bleach before trying to do a large one. Because last time I tried to do it I was having trouble with remaining copper left over in the solution. I am having the same problem with the test batches. Here is my procedure
-Filter A/P
-Remove as much non gold pieces as I can
-Procede to spray the filter(gold and all) in the funnel with a spray bottle, to remove the green colour.
-Pour hcl through the filter trying to remove any copper
-More water
-I then take the gold including the filter and put it in the hcl+B (I keep the filter in the solution because a lot of the gold is very fine and would be hard to remove)
-I don't have beakers so I use a measuring cup in a pot of boiling water to try to drive off the chlorine
-Boil for 20 min
Now after the boiling and letting it sit for a day, the solution still has a certain green colour about it. Could my method of heating the solution not be enough to remove the chlorine? I am getting some proper glassware soon. Or could the green tint be from remaining copper? When I used stannous it turned purple on the paper about 2 minutes after applying it. I don't know if it is supposed to be instant colour change or not. Any insight would be appreciated

mason

 

[Claudie]

You have the method wrong. Read through this thread: http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=52&t=12914

 

[kkmonte]

You shouldn't have any copper in auric chloride. You should only be dissolving gold with bleach and HCl. If you have copper and gold both dissolved, then I would add a clean copper buss bar, cement out the gold, collect the black fine particles (your gold) and then re-dissolve just these powders in HCl and bleach.

 

[masonwebb]

I read over it, and my washing procedure is not working well enough. I need to get my hands on some proper glassware. I should use more HCL to wash instead of water.

 

[patnor1011]

You shouldn't have any copper in auric chloride. You should only be dissolving gold with bleach and HCl. If you have copper and gold both dissolved, then I would add a clean copper buss bar, cement out the gold, collect the black fine particles (your gold) here I would add that I would incinerate them and then wash them in HCl several times till no colour change and then re-dissolve just these powders in HCl and bleach.

I started with pyrex pots from kitchen supply store and mayonnaise buckets.

 

[squarecoinman]

Hey guys so I have tried to do some small practice batches of HCL+Bleach before trying to do a large one. Because last time I tried to do it I was having trouble with remaining copper left over in the solution. I am having the same problem with the test batches. Here is my procedure
-Filter A/P
-Remove as much non gold pieces as I can
-Procede to spray the filter(gold and all) in the funnel with a spray bottle, to remove the green colour.
-Pour hcl through the filter trying to remove any copper
-More water
-I then take the gold including the filter and put it in the hcl+B (I keep the filter in the solution because a lot of the gold is very fine and would be hard to remove)
-I don't have beakers so I use a measuring cup in a pot of boiling water to try to drive off the chlorine
-Boil for 20 min
Now after the boiling and letting it sit for a day, the solution still has a certain green colour about it. Could my method of heating the solution not be enough to remove the chlorine? I am getting some proper glassware soon. Or could the green tint be from remaining copper? When I used stannous it turned purple on the paper about 2 minutes after applying it. I don't know if it is supposed to be instant colour change or not. Any insight would be appreciated

mason

There is some information missing.
I assume you started with a given amount of fingers in the AP tank, that had 30 % hcl and 3 % peroxide and maybe also a air pump connected, you left that for a period of time ( between 2 days and maybe a week ) and did stir when ever you came near it.
After this time period all the foils where loose and you filtered this .
this gave you a green filter with gold foils in it . You then sprayed the filter with ? ( water ) so that you had a clean filter ( no more green ) and clean foils ?
where did the water that you sprayed on the filter and foils go ?

I don´t understand why you put the filter in the solution, yes there maybe some very small gold still on and in the filter , but most can be sprayed of and then keep the filter in your filter pile that you can burn one day when you have enough. by keeping the filter in your HCL and bleach you bring in a foreign element, and when the chlorine will dissolve your gold it will also go in to the filter. It may even take up a lot more gold then it had before.

After you have washed the foils in clean water, you should have a tea spoon or more of foils, put them in a jar and use very little HCL, then add a very small amount of clorox / bleach ( make sure you do not have the wrong additives in your bleach ) wait a few minutes and add some more ( repeat this if needed ) ( remember safety )

when you did this was there any colour ? and if so what colour ?

I do not boil my solution, there is no reason for that, it has to evaporate, placing the jar a few hours in the sun will be enough ( if you do not over use the clorox )
wait until next day and it will be nice yellow colour.


scm

 

[Claudie]

I think what may be happening here is you are pouring water or acid over the foils in the filter. To do a proper washing, you need to put the foils in a container and cover them with solution, and then filter again, not just pour acid over them in the filter.

 

[Geo]

foils will always be contaminated. it usually occurs with pins.as the base metal is digested from the open end,the acid has to travel farther down this gold tube in both directions.as the tube collapses, the base metal trapped in the very tip remains undissolved. other than that, metal salts are very hard to just wash off.

 

[masonwebb]

I think what may be happening here is you are pouring water or acid over the foils in the filter. To do a proper washing, you need to put the foils in a container and cover them with solution, and then filter again, not just pour acid over them in the filter.

That is definitely the main issue, I need to perfect my washing technique. As well as use as little oxidizer as possible to get the foils to dissolve. I had never thought of trying to spray off the filter like spraying the gold off the spent fingers.

I also picked up some chlorine test strips from work, they tell you the amount of chlorine in a solution.
On another note I am going to pick up some sodium hydroxide to remove solder masks, those plastic pieces drive me insane!

 

[squarecoinman]

Mason Lazersteve has a good video on how to remove soldermask, but hot sodium Hydroxide is dangerous stuff, acid will very fast be neutralise's when it enters your eyes or body sodium Hydroxide not, it will keep on going. So do use a mask, goggles etc etc.

If you think it is to dangerous, I have some good results with plain water and cooking / boiling for some hours. Steve´s method is much better and faster, however a soft boil for 5 hours will do the trick for 90 % without the Sodium Hydroxide. also after you dissolve the gold in chlorine , you put the liquid through a filter and all the green stuff is gone.

scm

 

[masonwebb]

Heres an update for my progress!

I removed the gold from 20 ceramic plates and cups, they were heavily coated on the edges. I used HCL+bleach to remove it, and it worked amazingly! Within 10 seconds all the gold was removed. I fashioned myself a hotplate from an old restaurant coffee machine, I took pictures and I think Ill post it as a guide. It was really simple!

So I placed the beaker on the hotplate and proceeded to evaporate half of the solution. Stannous was positive so I added the SMB and nothing! Just a little fizz and a nasty odour... Starting to think my SMB is bad!

How do you use copper to cement? I have some copper pipe, is it as simple as placing it in? Is it an immediate reaction like stannous?
***EDIT***
I searched and found the answer!! Thanks to butcher :lol:

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=18347&hilit=using+stannous+to+cement&start=