Is it vital after evaporating down Au solution to 25%

[bklopsy]

of original, to add additional HC1 to expel oxidizer (nitrate.) Is this more of a step for purity of the gold or is this an issue pertinent to precipitation?
Brooks

 

[lazersteve]

Brooks,

The step is required to remove nitric acid prior to adding SMB so your gold will precipitate readily.

Some tricks to eliminate the required boiling down are :

1. Add your nitric in small controlled increments so as not to add too much to begin with. This is the most desirable method in my opinion.

2.Add a solid gold button to consume the remaining nitric.

3. Use urea to neutralize the excess nitric. This is the least desirable method in my opinion.

Steve

 

[goldsilverpro]

Steve,

1. Add your nitric in small controlled increments so as not to add too much to begin with. This is the most desirable method in my opinion.

If you and I could ever get that important point across. It is so simple.

 

[lazersteve]

Chris,

I think the real problem is impatience. Everyone wants fast results so they add in more nitric/peroxide/clorox than they need. Then they end up with gold that won't drop and spend hours or even days removing the excess oxidizers.

This is where a little math on the front end will save both time and money on the back end.

Steve

 

[bklopsy]

Steve
I took serious shortcuts from your "poor mans AR" and am learning the hard way. I boiled down solution to 25% then added equal volume of water and attempted to precipitate.
Just like your video, the solution started to go clear (not completely) then started turned brown but gold still not dropping.
I live in CT and it is pretty cold outside this morning. Is it best to simply add heat or more HC1 (at this stage) or both.

Thanks, Brooks

 

[bklopsy]

Just read feedback from other post and am experimenting with copper. I am a contractor and the only copper I have is a plumbing connector which is an alloy. Is this OK???

Brooks

 

[lazersteve]

Brooks,

As far as I know most all copper pipe is pure copper.

Copper pipe should do fine.

How much scrap did you process?

Steve

 

[bklopsy]

I just sent you a responce under "I want to do it right this time" Post. I removed that copper from the same solution because it was forming what appeared to be silver chloride. Grey not brown or black.

Any suggestions

Brooks

 

[lazersteve]

Gray sludge form solutions is likely copper I chloride.

Copper I chloride will redissolve in excess HCl.

Steve

 

[bklopsy]

Steve

Gold dropped while I was evaporating third attempt. While heating, I added a little urea. It barely fizzled. That was enough for me, I added two tablespoons and stirred a few times. Came back twenty minutes later and the drop had occurred

Thank you

Brooks