Sciencemadness Discussion Board

Colloidal gold from old electronics.

vano - 6-9-2022 at 11:43

Hello! I made some colloidal gold solution. also very easy to make at home. it needs just acids and old electronics, but very small amounts are necessary. first, I added conc. nitric acid to gold-plated components, as you see not much. then made gold foils and add less than one gram of mercury, when I dissolved it in nitric acid I get this funny amount of gold(PICTURE 2).

IMG-2222.jpg - 1.6MB IMG-2229.jpg - 1.3MB

then I added maybe less than 2ml aqua regia. I diluted the chloroauric acid solution and add carbonate at the same time I was heating it.
The solution got this color (PICTURE 4&5). I did this experiment on a plate because a large area is important. there are some gold particles because I didn't filter it.


IMG-2236.jpg - 2.1MB IMG-2238.jpg - 1.8MB
IMG-2237.jpg - 958kB

[Edited on 6-9-2022 by vano]

[Edited on 6-9-2022 by vano]

Pumukli - 6-9-2022 at 22:06

Looks good.
But why use mercury?
YT is full of "recovering gold from old electronics" videos - but none of them use any mercury... They simply dissolve other metals with nitric acid then dissolve the gold in aqua regia.

vano - 6-9-2022 at 22:35

There was very small gold foils particles, polymers waste. So i collect all gold with mercury.