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Comment by danrecht | Hacker News Reader

Collecting small things from many sources over meaningful distances is hard.

Separating things made of many materials is hard, especially when some components are hazardous.

Purifying materials drawn from waste is hard.

These aren’t impossible challenges, but physical facts of the problem that have kept costs too high for electronics recycling to be widespread.

Longer lasting electronics that can be repurposed or reused is the lever I’d be most excited to pull here.

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At some point in the 90s I remember hearing an NPR story about a new startup that was "pioneering" technology that would basically permit atomic/small-molecule level "cat cracking" of just about anything: a furnace that was so hot that everything put inside it broke down to atoms/small-molecules which could then be fractionated off for re-use.

I was so excited. I was so naive.

The idea seems to have gone nowhere.

That one seems like it should fall foul of thermodynamics, I guess. Just melting everything together probably increases entropy to the extent that it's at best like extracting elements from mining ore. Whereas before you do that, there is organisation and substances are more concentrated. Well, that's a bit hand-wavy - perhaps someone with actual knowledge of thermodynamics will comment.

I think what recyclers do currently is at least break everything into small pieces, some of which might have a decent concentration of something useful

Nothing falls afoul of thermodynamics. This is not a closed system - you can inject as much energy into as you have available. Entropy and thermodynamics play no role here, but I would imagine that (a) the cost of the energy require (b) containment technology (c) what happens after you extract a given substance are/were all very involved in its failure.

This is already done with crude oil, and is called "cat cracking". You heat the crude oil until every component in it becomes gaseous (but still small-molecule) - the smaller the molecules they higher they rise up the "chimney", so you can siphon off particular components at particular heights.

I wasn't arguing that it is impossible, which as you say, is only true in a closed system. What I was saying was that since you wasted the organisation of the system, sorting it out again is going to take more energy than if you didn't. I think that's a consequence of the fact that you increased the entropy.

It'd work fine if you just ionize everything; easy to separate then. Just hilariously inefficient given the amount of energy required.

And even if you can collect those ions to relatively high purities. It is not often particularly useful. Most of the mass is probably carbon, silica, oxygen, hydrogen and so on. In the end not that much value there compared to virgin or other sources.

The Empire Strikes Back: scene where Chewy rescues C-3PO's parts from going into the recycling furnace.

Depends on what you are trying to recover. Recovering precious metals from electronics is no more difficult than processing precious metal ore.

Which comes back around to logistics and scale: refining ore is cheap because ore is delivered on multiple 300t haul trucks or in giant trains

I wonder if part of it is also that mining companies are generally allowed to just leave their tailings in a big pile near the mine rather than have to responsibly dispose of the majority of the ore that has no (or negative) commercial value.

I think that plastic parts, such as enclosures for electronic devices, should have resin identification codes moulded in them — just like plastic packaging does, so they could be recycled too within the same system.

Except that despite those codes on plastic packaging, almost no plastic packaging gets recycled. Most of what you put in the recycling bin just ends up in the landfill. The plastics industry has been scamming us on this point for years.

> Separating things made of many materials is hard, especially when some components are hazardous.

Make the tech giants building robots solve this problem first.

> Longer lasting electronics that can be repurposed or reused is the lever I’d be most excited to pull here.

Capitalists are pulling the lever in the other direction, though. And there's many of them. Or they pay people to pull.

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