What You Will Need
Two - 5 Gallon Buckets
Wire Mesh Holder
1lb Sub Zero ) from Shor International
1/2 gallon of muratic acid aka hydrochloric acid
Precipitant ( from Shor international)
Gold Detection Liquid (from Shor International)
Urea Distilled Water Aqua Ammonia (from Shor international)
This process involves working with corrosive chemicals and may produce potentially hazardous fumes and by products - so make sure you wear googles, a face mask and that you are not doing this in an enclosed space,
Cut off the parts of the circuit boards that have gold and place them in the bucket. Throw away the other parts of the board. If you have CPU chips you need to break them open as the gold is usually inside the chip. Put these in the bucket.
Take a 5 gallon bucket (make sure its clean)and add 1lb of the sub zero to 1/2 gallon of muratic acid. Virtually all the subzero should dissolve into the acid liquid.
Place your CPU chips and cut up boards in a plastic wire mesh basket and then place this in the liquid in the bucket. The gold dissolves into the acid giving off off brown fumes. (these fumes are toxic so make sure you are doing this process wearing a face mask or in an open area!) This process can take up to 2 hours. Come back after 2 hours and check the boards to see that all the gold has been dissolved into the liquid.
Once the acid liquid is no longer reacting then take out the basket and check the liquid to see if any lumps of other material still remain in the liquid. If there are lumps or other materials then filter this liquid or simply decant it into another container leaving the solid lumps behind.
Your acid liquid should be a clear,dark green color, if it looks cloudy then filter it until it is clear. Once it is clear, add urea to the acid liquid little by little. It should react by fizzing - keep on adding the urea until the liquid no longer fizzes.
Once the liquid has stopped fizzing,add precipitant to the acid liquid to extract the pure gold. You will need approx. 1.5 spoonfuls of precipitant for every ounce of metal dissolved so remember to roughly weigh what you dissolved at the beginning. Add the precipitant to a clean bucket and then add the acid solution. The precipitant and the acid will react creating a muddy solution that sinks to the bottom of the bucket.This mud is your pure gold! To establish whether you have extracted all the gold from the acid liquid using a gold detection liquid- test some of the acid for gold content (if there is any gold in the acid still the gold detection liquid will turn purple brown). If there is still gold in the acid then add more precipitant.
The acid liquid should now be a clear green or amber color with mud lying at the bottom. Pour off the acid into another container leaving only the mud. When the acid has been poured off add 2 or 3 gallons of distilled water to the mud to rinse the acid from the mud then pour off the water making sure you dont pour off any of the mud ( you may want to use a filter). This rinsing ensures the high purity of the gold. Test the mud with aqua ammonia for the purity of the gold. If it turns blue then you need to keep rinsing.
Once you have established the purity of the gold then you have your mud or powder, melt the powder and you will then have your pure gold.
Disclaimer: This information is not professional advice, it is merely a description based on my own experiences,