Extracting Gold from Vintage PCBs

[HPRecycle]

I'm currently looking for some help with extracting gold from vintage PCBs. They are military grade from the 70's taken from an HP spectrum analyzer. I have between 20 and 30, ranging in different sizes. On the other side is gold beneath the solder resist. Below is a link for an image of one of the circuit boards (Too large to embed):

http://i.imgur.com/6sB7mtA.jpg

The main questions I have are:

- How much gold should I be expecting to receive from each board?
- What is the best method of extracting the gold?

I'd also like to add that yes, I have done some research however I'd like to receive more specific advice. Thanks.

 

[kurtak]

You joined the forum & about 30 minutes later ask what amounts to one of the first most common questions asked by new members - therefore I will point you to the very first thing you need to read concerning how this forum works - click on this link :arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=19074

please understand I am not trying to put you off &/or discourage you --- once you have spent "a fair" amount of time doing some "real" research & have some real knowledge under your belt we will be more then glad to help you

Be sure you read Hokes book - its a free down load here on the forum - it doesn't have info about process electronic scrap (that info is here on the forum) but it (Hokes) will give you the basics of what you NEED to know before you can even get started

Kurt

 

[lanfear]

I agree with Kurt. These boards look really nice, and there are a 100 different ways you can loose that gold if you don't know what you are doing.
You also need to read up on the safety section and how to deal with your waste acid. Once that acid contains metal ions it is poisonous.
If it were me I would remove the component by hand and sort them. Then you need to search the forum for "remove solder" and study that.
And then you can search the forum for "remove solder mask" and study that.
And then you can search the forum for "acid peroxide" or "AP" and study that.
And also search for "stannous chloride" and study that.
You will need to have a good grasp of all these topics before you consider anything. And when you do start with a small test with 1 board.
And read Hoke!
Good luck

Jon

 

[eastky]

Surface area calculations. How many square inches of gold plating on the boards you have. Total square inches divided by 100 to equal 1 gram of gold. Doing that also depends on how thick the plating is.