Help with acid-bleach method!!!!

[rontrusi]

Here's the quick lowdown on what I've done so far......
I did the AP method of harvesting the fingers off of boards and from a few header connectors as well. Just to be sure, I redid the process to try & make sure I had mostly gold. After I was finished I was quite surprised to find out I had about 35 grams worth of material!
Well, I just tried doing the acid-bleach method to dissolve the gold into solution and instead of the nice golden color you would expect, mine is a nice emerald green!
I guess my question is....why???? I did the AP twice to make sure I got rid of all the other metals & still ended up all screwed up. In Lazersteve's video he did approx 3 grams of material which looked to be about the same volume as my 35 grams is. Maybe it's just a visual perspective thing. How much acid-bleach should you use per gram of material?
Finally the main question is.....should I just try and drop the gold with SMB now even though it's green instead of golden?

 

[JustinNH]

How many grams (or lbs) of fingers did you begin with? Must be a ton to get 35 grams after.

Also, after AP, what is left should be only the tiny gold foils (and maybe some fine black/brown gold that was taken in and dropped out by base metals) is that what you are seeing for your 35 grams?

You don't need to do AP twice. Once is enough and if it slows down, add a tiny bit more H202 and it will start going again, or rejuvinate with an air system (all talked about on posts here).

Also, don't mix fingers with anything else, its best to sort and process things individually. Having other things puts more base metals in.

I think (not sure)the green is from copper or other base metals mixed in. Drop out the gold and repeat the HCL-CL/wash really well, as there will be base metals in the precipitated gold the first time. There are also plenty of posts here on this as well.

For the how much clorox to HCl... start with the foils and enough HCl to cover them nicely. Slowly add small amounts of the bleach (too much will waste the chlorine and create salts) give it time to work and eventually all the foils will be gone and you'll have the pretty auric chloride. Wait a little bit for the chlorine gas to calm down before you drop with SMB too.

Hope that helps or atleast gives you some ideas.

:wink: What say the pros?

 

[rontrusi]

The foils look pretty decent....mostly gold with a little bit of black whatever-it-is!
Well...I'll go ahead & dissolve the rest of my foils (I only did about 6 grams worth the first time) and let it sit overnight to get rid of some of the chlorine.
As long as I'll be able to drop out the gold with SMB with no problems I'll be happy. I planned on dissolving it out twice anyway to purify the gold. Maybe I'll have to do it three times now!!!
So does this seem to be the general consensus out there? No harm...no foul??

 

[skoorb]

did you wash the foils in straight hcl a few times? According to the video you should wash them until there is no color change.

 

[rontrusi]

Yup, sure did. I did it several times just to be sure.
Maybe I just have so much doggone high quality gold in solution that it's gone beyond gold colored to a REALLY dark gold that only looks like it's green!!

 

[lazersteve]

After I was finished I was quite surprised to find out I had about 35 grams worth of material!

Did you weigh the material wet or dry?

Did you wash the material in HCl until the acid no longer changed color?

Did you follow the HCl rinses up with several water rinses?

mine is a nice emerald green!

This answers my questions above about washing, you didn't or you were not very through with your washes. The color is from dissolved copper. Follow the steps outlined in my AP video and you will not have this problem. Also be sure you remove any large debris (copper scrap pieces, wires, etc).

When using HCl-Cl the trick is to cover the properly washed material with HCl, then add very small amounts of clorox with lots of stirring. When you think you've stirred it enough, stir some more. Once you no longer see bubbles or smell chlorine gas (choking smell), add another very small amount of clorox. Repeat this with lots of stirring and then more stirring. Heating on low heat helps dissolve the material, but increases the off gassing.

The stirring exposes the gold foils to the chlorine gas. Too much clorox and you will have lots of out gassing and the gold , once dissolved will be stubborn to precipitate.

Steve

 

[rontrusi]

Did you weigh the material wet or dry?

Did you wash the material in HCl until the acid no longer changed color?

Did you follow the HCl rinses up with several water rinses?

Steve

I weighed it dry.
Yes, I did several HCl washes until no color change but I didn't do several water washes.... I did one quick one.

I ended up using quite a bit of bleach in the HCl because the foils wouldn't all dissolve (I had a bunch of them remember). I've got a bunch of liquid after finishing up all the foils. I'm going to let this sit outside for a day or so to help it outgas. Then I guess I need to dilute it down about 4:1 with water before trying to precipitate the gold.
Do you think I'll have a problem dropping the gold after all this?
Obviously when I'm finished precipitating I'll need to dissolve it all again with acid-bleach and do it all over again. Do you think it will all turn out OK after this? Just a lot of extra work I'm sure.


[img:640:480]http://www.fileden.com/files/2007/7/16/1269763/DSCN0226.JPG[/img]

 

[lazersteve]

The photo shows your strainer with filter is very dark colored. When your foils are properly washed the filter will be completely white with no discoloration.

I don't see any reason to dilute your solution any further as it looks diluted already.

After you get it the base metals out the resulting gold should be fine. I would definitely wash, incinerate, and redissolve the resulting gold powder.

Steve

 

[rontrusi]

Actually the filter is clean...they're brown filters to start with...not white. The parents left them out here when they left (they drink coffee, I don't). I was too cheap/lazy to go buy white ones!

 

[rontrusi]

Well, I tried precipitating out the gold with SMB & got absolutely zip, nada, nothing! I'm almost to the point of just flushing it all down the toilet. I thought some gold might drop because it look like a golden cumulo-nimbus cloud in the solution but then it went away & nothing else happened. I'm sure I used too much SMB after trying to get it to do something.
What can I do to get the gold drop out. I've tested it with stannous & it shows there's gold in them thar hills!

 

[butcher]

if you are sure you have gold in solution add a little HCL and a good boil,and with enough SMB in solution you should see your gold, if all else fails you can replace the gold with copper in solution.

 

[qst42know]

There is no need to call it quits, and if you did it wouldn't be right to send it down the toilet. It can wreak havoc on treatment systems both public and private. If you are on a municipal sewage system they may come looking for the source.