Debayan Pyne
Member
- Joined
- Jul 31, 2020
- Messages
- 9
I've tried to conduct the experiment of gold recovery from electronic waste. I used 3kgs of Intel Pentium 4 processors along with others for this purpose and initially the material seemed descent just for this experiment and not for any profit motive. I dismantled the whole lot and washed them properly with hot water. Then I gave them the first chemical bath with 32% hydrochloric acid and 3% hydrogen peroxide in 2:1 ratio (about 1lt hcl and 500ml h202) to detach the gold coated foils and pins and kept it for 48 hours. Then I prepared my stuff for aqua regia. I dipped the residue in a solution of 32% hydrochloric acid and 70% nitric acid in 3:1 ratio (about 150ml of hcl and 50ml of hno3 along with 50ml of distilled water) and kept it for 24 hours after which I added some urea to neutralize hno3 and poured in a solution of sodium metabisulfite (mixed with hot water). Drained the rest solution and I got some brown mud like stuff sitting at the bottom of the beaker. Then I washed the thing with hot water, boiled it, filtered it and dried the filter paper. I got some black dust. I don't know what it is and where the gold went? I don't know what went wrong, I'm new to this and this is my first experiment on gold extraction. Can anyone please help me.