As far as I understand it, electronics are recycled by crushing them and extracting a handful of minerals - e.g. gold, there's more gold in circuit boards than the rocks they dig out of gold mines I've heard.
The rest - which by mass, of course, is something approaching "all of it" - is mostly toxic fibre glass, epoxy and plastic that we don't really know what to do with. It's bad, even before you start talking about all the electricity and heat that was used to turn it into electronics in the first place.
My significant other worked in a recycling plant. To elaborate on the "rest" and how it is done:
PCBs get delivered, sometimes without big components (coolers, screws/brackets fans removed), but also sometimes with those. They are shredded as a whole, including all soldered components, to a particle size of 2mm. Iron and aluminium are separated magnetically (in case of aluminium with an eddy current separator, iron with a static field). All three components, mostly-iron, mostly-aluminium and the rest are then melted down separately. Adherent plastics, electrolytes, epoxy, etc burn off during this process. Gas and ash are lead through separators that filter out the fly-ash as much as possible, which is buried somewhere as toxic waste, the rest is entered into the atmosphere after cleaning (afaik various liquids to bubble through to wash out soluble chemicals, which are then dried and buried). All three metalllic liquids are then metall alloys of various purities which are then cleaned and separated further by skimming off the slag, adding flux, electrolysis and other chemical separation methods. Most of the "other" fraction is copper, which is the main product overall, other rare metals such as gold occur in far smaller amounts and seemingly add only a little to the overall earnings in the process.
Please note that this is the process used in a relatively new plant in a Western European nation. I guess the "advantage" over the rest of the world is that at least there is a fly-ash separator and exhaust cleaning.
Actually, there are companies working on PCBs based on organic, water-soluble substrates [1] - to recycle a board, you boil it in some hot water and get a liquid stream containing the substrate and a solid stream containing the electronic components and copper traces.
Which is a researach-stage idea with obvious drawbacks: Moisture in air will also slowly decompose PCBs, making them age much faster than traditional epoxy-based PCBs. So then you either limit the maximum age of all your products severely (not very green) or you need additional materials to moisture-proof all your casings (also not very green).
Do you really think that they haven’t spent at least as much time thinking about this? The question would be whether those devices are replaced in less than the time it takes for natural degradation to cause problems, and both of your “not very green” dismissals sound entirely too pat. The entire reason we’re talking about this is that the industry has a huge problem with things having a service life measured in single digit years and a landfill life measured in centuries – making those easier to recycle would be a huge win because there’s no way that the current model is going to get the service life significantly closer to that kind of timeframe.
> The research will also provide Infineon with a fundamental understanding of the design and reliability challenges customers face with the new material in their core applications.
It sounds more like they know that this is a hard problem requiring foundational research, and suggests that rather more thought has gone into it than a quick HN comment dismissing their work.
While there are probably more modern servers around now than ever before, from browsing serverhunter.com there seem to be a couple of cliffs where older CPUs gets rarer, one at 2017 and one at 2014.
If by recyclable you meant buying old racks of datacenter servers to reuse elsewhere, even if possible, it's not very practical. Servers are super noisy and may have exotic power requirements.
