In more than one occasion, we have talked about the challenge of electronic waste. Besides the polluting potential of some components, we must also consider the precious metals (and others not so much) that are used in their manufacture and end up in the landfill. If the scale is appropriate and the economy of the moment helps, the extraction of metals such as gold and silver from old computers and phones becomes the main reason for general hardware recycling.
Over time I have given away some computers, and I have also taken components for recycling. A life close to hardware makes the accumulation about to get out of control on more than one occasion, and if I look around… I think I should keep cleaning. The great dilemma is knowing for sure where all that ends up. In no way am I interested in a motherboard ending up next to an empty milk carton, but that seems to be the rule these days.
Big companies talk about a "commitment to the environment" and organize things like return programs, but at the same time they feed the furnaces of planned obsolescence, thus transmitting an empty message. The most complete recycling processes do not have ecological protection as their main priority, but something much more tangible: the recovery of precious metals.
Getting Gold from Your Old Hardware
The main elements are copper, silver, and gold. Recovery begins with manual disassembly of each computer and monitor, sorting the parts according to their type. Processors are the "easiest" to recycle, so to speak. A mixture of nitric acid with hydrochloric acid (what is usually known as aqua regia) dissolves hundreds of chips at once.
It is very difficult to calculate the amount of gold that will be extracted, since this depends on the type of chip and its age (for example, old Pentium Pro processors are highly sought after by recyclers). The "gold dust" obtained is washed and melted to create ingots.
The rest of the components demand a much more complex process. After removing each metal piece from the boards, the result is melted, creating an alloy of copper, silver, and gold. This alloy is cut into sheets, and with the help of an electrolytic system, first copper is extracted, then silver, leaving pure gold at the end.
It is most likely that the recovered metals go directly back to the production line to create new computers, although the video mentions "gold salt". Needless to say, if someone wants to reproduce this on a smaller scale, they must be very careful with handling acids, and of course patience… but it works.
https://old.neoteo.com/extraccion-de-oro-de-placas-base/
