Fun with Concentrated Hydrogen Peroxide and Pins

Art Corbit · Apr 21, 2008

Hi Steve,

Please excuse a couple or four stupid questions here. Exactly what do you mean by keeping my scrap separated? Don't mix the boards with pins or fingers or what? I also need to know what you mean by "AP & SMB" I think I know what the SMB is but not sure.

I didn't get any pictures but I plan on running another small batch today and I will. The solution was a real dark green. It dissolved a lot of the coating on the board. I am also going to start out with full strength HCL and only add a small amount of Peroxide. I sure don't want to dissolve any more of my gold.

Art

Art

lazersteve · Apr 21, 2008

Art,

Follow the Guided Tour link in my signature for some definitions and other info.

Process the various types of scrap separately. Mixing types of materials just complicate the process. Test small batches to determine which type work well with Acid Peroxide (AP).

Sodium Meta Bisulfite (SMB) is a common precipitant for gold.

Steve

Art Corbit · Apr 21, 2008

Thanks Steve,

I thought that is what they were but I wanted to double check to be sure. Also I didn't remember if the Sodium Meta Biosulfite was sul-Fite or sul-Fate. If I remember correctly there is both. I have been trimming the gold off the boards pretty close to keep all the green crap out I can. I don't try to do the pins and the board gold together. I have been using only small amounts just testing but it seems either it doesn't work at all or it dissolves the gold first. The Gold is long gone and the copper is still there undissolved. I have never run into that before. Looks like my next step is to see if I can find some sodium Nitrate and mix me up some poor boys Nitric and try it. I'll be hanged if I'll drive 300 miles round trip to get the real Nitric. That would eat up a bunch of the profit.

Art

67eod · Jul 30, 2008

What product name do they sell the H2O2 and HCI under.

Thanks Bob

geekzilla said:
After watching Steves video on the AP process with gold fingers, I too began to wonder if a more concentrated HP solution would yield quicker results. Thanks for trying it out and posting your results.

Incidentally, I have found an online supplier for H202 that has flat rate shipping to anywhere in the US for $9.95 (they also sell HCl)! Here is the link:

http://www.pondepot.com/index.asp?PageAction=VIEWPROD&ProdID=3161

Oz · Jul 30, 2008

Hydrogen peroxide = H2O2
Muriatic acid = HCl

goldsilverpro · Jul 30, 2008

You can buy 3% hydrogen peroxide at any grocery store or pharmacy or Walmart and HCl (muriatic acid) at about any hardware store. They are about the easiest needed chemicals to find.