How to Recover Gold From Circuit Boards
Many of the connectors on circuit boards are coated with gold to improve electrical conductivity. Granted there's not very much gold on any one board, but if you have access to several dozen or (better yet) several hundred of circuit boards, then it is possible to remove and recover enough gold to make it financially worthwhile. There are several different methods for recovering gold from circuit boards, but for the average person a hands-on approach should prove to be the best method.
Things You'll Need
- Picks (like dental instruments)
- Needle-nose pliers
- CBX powder
- Eye goggles
- Two glass or ceramic bowls
- Wooden spoon
- Plastic coffee filter
- Crucible (optional)
Collect as many circuit boards are you can. Recovering the gold from one or two boards is not economical --- the more boards you have the better.
Remove all metal from the boards, especially the connector "fingers." Fingers are the flat gold-colored pieces lined up in a row along the edge of a board which connect the circuit board to other parts of the computer. Use tweezers, dental picks and needle-nose pliers to separate the metal from the circuit board itself. This can be a tedious process. Place the metal pieces in a large glass or ceramic bowl. Discard the nonmetal pieces of the boards.
Empty the contents of one jar of CBX powder into the bowl with the metal circuit board pieces and then add one gallon of water. Stir the mixture with a wooden spoon until all of the powder is dissolved. Wear gloves and eye goggles when mixing the CBX powder as this is a powerful acid. Allow the metal pieces to soak in this solution for eight hours.
Place a plastic coffee filter into the other glass or ceramic bowl and pour the CBX mixture through the filter, raising the filter up as the bowl fills with the liquid. While wearing gloves, remove the metal pieces from the bottom of the now-empty CBX bowl and hold them over the filter while rubbing them gently together and pouring water over them to remove any last traces of CBX-loosened gold.
Remove the gold from the coffee filter. If desired, the gold particles can be placed in a crucible and melted.
Tips & Warnings
- Always wear gloves and eye protection and use extreme caution when using CBX in any form.
- Run plenty of clean water into your sink while slowly pouring the used CBX mixture down the drain.