Original URL: https://www.theregister.co.uk/2011/11/02/recycling_your_high_tech_gear/

Is your old hardware made of gold, or just DIRT?

Why it's not worth much, unless it's really old

By Tim Worstall

Posted in Data Centre, 2nd November 2011 11:30 GMT

So you want the money to pay for the office Christmas party, naturally. We're all told endlessly that all those piles of old electronics and high tech'n'stuff are denuding the planet of valuable metals, so you should be bundling up your kit and sending it off to people like me who will melt it down for the dosh, yes? I'll send back a brown envelope or two of cash and it's trebles all round!

Well, yes and no: this does work for old kit and almost certainly doesn't for new. By old here I mean the sort of stuff you threw away decades ago.

A couple of technical points about metals and recycling. The first is that, as I've said here before, ordinary stuff with metals in is generally known as “dirt”. When the value of the metals is greater than the cost of extracting the metals then dirt becomes “ore”. This is an economic concept, not a geological one and as with such economic concepts it applies much more widely than just to piles of rocks lying around under some foreign field. It applies to all that expensive iron that you lot have littering your offices as well. It may be made of various metals, you may have paid a lot of money for it, but when you no longer need it to push electrons around it might be either dirt or ore.

The second point is that the economics of recycling (the recycling of anything at all) work the other way around than the usual increasing unit value from wholesale to retail that we're used to. We usually think in terms of each PC in a container of PCs having a lower value than one single PC on a retailer's shelf just where you want it. Recycling runs the other way: unit values increase as you have more units.

The PC's interior, caked in dust

Is this dirty dirt, or dirty ore?

As an example, think of the catalytic converter in your car. There's maybe a gramme of platinum in it (usually, something like a gramme per half kilo brick of zirconia, a Fiat 500 having one brick, a big Jaguar maybe 8) and platinum is currently $1,500 a troy ounce or so. Call that $50 for the Pt in your car then (or $400 in that of the fat cat boss - and no, troy and avoirdupois ounces, just not important here).

So, can you clip the converter off the car of the bird next door and get $50 for it? No, you most certainly cannot. You'd be lucky to get $10 for one. But if you had 100 of them, you might well get $15 each and if 2,000 then you can actually take them to the refinery (Johnson Matthey, Cheshire, for those who desire to know) where you'll get the Pt value, minus processing costs, plus they'll also pay out on the palladium and rhodium contents. Scrap values increase as you have more units.

So here we have our two basic rules which will help to determine whether flogging your old kit is a worthwhile dream. The more pieces you have the more scrappies like me are willing to pay for each piece: assuming that what you have is actually ore, and not just dirt. What determines the ore/dirt interface is of course which metals it has been made out of in what quantities.

As a general rule, newer equipment is less valuable than old, for these purposes at least. It really wasn't all that long ago, within my working lifetime, that the gold on connectors was a 200 nm plating. It doesn't sound like all that much but these things add up and old, say pre-1990 or so motherboards probably are worth melting down just for the gold. That you can reclaim tin, lead and copper at the same time can make it a very profitable occupation in fact. One cute trick was to melt the solder off (250°C to 300°C or so) and at this temperature the solder and the gold form a eutetic alloy. This you refine electrolytically, the gold is in the sludge on the bottom of the tank and the solder can be sold for a 10% premium to new material as it has been electrolytically processed.

Another example is that the gold in an 80286 was worth about $5 (more like $15 now at current elevated prices).

In fact, with old PCs, these pre-1990s say, get enough of them into a pile and they were ore, not dirt. However, if there's metal value when they're scrap, that means, obviously, that someone has had to buy the metal to make them and people don't like doing that. So the pressure has been to reduce the metals values that go in to the machines in the first place. That gold plating is more likely to be 2 nm now that 200 nm. The copper tracing is much thinner than it used to be, solder is placed much more accurately and with less of it. The modern PC is, if you look purely at metals values, much more like dirt than was its decades-ago predecessor.

There's only one way in which they have become more expensive and that's the banning of lead in solders. We have to use tin solders, not tin/lead now and as tin is worth much more than lead there's that one component that is pushing the value calculation the other way. That tin solder also grows whiskers (really, you can get a pointy “whisker” growing out of a majority tin solder which then shorts the circuits) is one of the explanations why modern electronics now fail before becoming useless rather than becoming useless (for reasons of software bloat) before they fail, as they used to.

Must get away from Chinese rare earths! Who here's willing to pull old hard drives apart for 25 cents a go? Well, the Chinese might ...

Much has been muttered about electronics and rare earths recently what with China playing silly buggers with supplies but here we're definitely on the dirt side of the equation. Neodymium is essential for the magnets in a hard drive motor: well, not essential, but the alternatives are more expensive and larger. However, there's some 6 grammes in each hard drive, meaning that you'd need to process 1 million hard drives to get 6 tonnes of the metal (and it's actually 6 tonnes of NdFeB magnet, not pure metal). At non-bubble prices of $40 a kg this doesn't really seem worth it: Anyone really want to hand pull (which you'd almost certainly have to do) a hard drive apart for maybe 25 cents a time? Yes, this is the dirt side of our barrier.

Metal Wires. Credit: UNEP

Ore, or ... ?

We've just had a report out about all of this, the recycling of metals in Europe. The report is here and it's rather good. It must be for it makes similar points to me. The reports about the report though are awful:

Recycling less than 1 per cent of high tech metals, Europe has no moral justification to blame the Chinese for restricting their exports of rare earths, Ernst Ulrich von Weizsäcker from the United Nations Environment Programme argued in an interview with EurActiv.com.

According to a report released by UNEP’s Resource Panel in the spring of this year, recycling rates of metals are in many cases “far lower than their potential for reuse”.

Less than one-third of the 60 metals studied in the report have an end-of-life recycling rate above 50% while 34 elements are below 1% recycling, the UNEP panel found.

No, that's nonsense. For reasons that the report itself points out: we recycle where it is economic to do so and do not where it isn't. Or to use my language, when the scrap is dirt we don't and when it's ore we do.

Take two metals, rhenium and terbium. They're both worth around $5,000 per kg, or at least they both have been recently, even if they're not that price today. We recycle most rhenium we use and almost none of the terbium we use. Re is used in jet engines, along with nickel and cobalt. Come the end of the jet engine's life, we've three nice valuable materials and we dissolve the lot and separate it all to make new alloy. We're also scrapping our jet engines in nice centralised locations so we accumulate the stuff. The other use is alloys with platinum in oil refineries and yes, of course we recycle that stuff.

Terbium however is used for phosphors on CRTs and in compact fluorescent light bulbs. We're talking milligrammes per light bulb so we're back to wanting a million bulbs to get our kg worth perhaps $5,000. And the bulbs mustn't break or the Tb will be lost to the environment. Tb's Clarke number (prevalence in the Earth's crust) is 1.1 or so, meaning 1.1 parts per million. Our pile of lightbulbs isn't all that far away from the Tb concentration of the vegetable patch which is why we tend not to mine either for Tb. Rare earth ores (not rare, as we all know) can be 0.09% by weight to 0.9% by weight Tb, orders of magnitude higher than the lightbulbs and thus we get our Tb where it's easy and cheap, not from recycling.

Even metals that we think we really are seriously short of we don't recycle if our use of them is to disperse them. Tellurium really is rare, 0.001 ppm in the crust, and we use it to make solar cells of the First Solar type, Cd/Te. But we don't recycle the cells, not even the factory failures, for the Te content. That content is so low that it is still cheaper to go and process some more copper slimes (no, really, proper technical word!) and no, we're still not going to run out of the metal. For everyone forgets just how big the Earth actually is. Six times 10 to the 24 kg, some 2% of it is crust. At 0.001ppm Te in the crust, we've still got 120 million tonnes of Te and we're using 125 tonnes a year. Chuck it mate and get some new in.

But all of this, while interesting, isn't telling you guardians of the hardware how to pay for the Christmas party is it? I'm afraid that for your standard kit your WEEE compliant contractors are still going to charge you for hauling it away. Yes, much of it does get recycled and the metals extracted, but that's because the law says they must. The process as a whole costs more than the metals value extracted which is why you've got to pay the difference: although do make sure your contractor is giving you a credit for that reclaimed value.

Three other things you can do though: nick everyone's smartphone and sell it to the people advertising on the TV (as with all such things, if you've got a bucketful, you'll get a higher price for each). If you're not already doing it you should be selling your empty printer cartridges. Yes, they can be valuable and bucketsful of them ditto.

Or, finally, have a rootle around in the back cupboards and see if you've got any really old kit. Hard Drives for PDP 11s for example, they were made of AlNiCo magnets, great girt lumps they were. Many a scrap dealer will take those off your hands for readies. Did someone buy in a stock of 8087s at some point and they're still rotting long after the last XT has left the building? And anyone out there with an analogue telephone exchange can have his choice of new digital ones for the gold content.

Entirely happy to help anyone with old kit or cartridges: the phones you'll have to fence on your own. ®