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  • It's quite difficult to get into places like this. You have to remove everything metallic. I'm not even wearing a belt.

  • I'm a bit worried that my trousers might fall down, that would be a first for Periodic Videos

  • I'm really excited. I've got here more than one and a half million pounds' worth of platinum group metals.

  • never had so many in front of me all at once

  • and we're here at Johnson Matthey Noble Metals and they've allowed us to see

  • all sorts of parts of the factory but just to warm up

  • as a sort of side show we have here five kilos of gold

  • and another five kilos in a packet.

  • These are each worth £150,000, so reasonable house just to get started.

  • We're here at a place where they're processing these metals here:

  • Rhodium, Iridium, Palladium and Platinum.

  • And the reason that they're called noble metals

  • is that they don't react with oxygen easily

  • In fact platinum is one that really even at high temperatures doesn't form oxides

  • the other ones can form oxides

  • Gold doesn't form oxides, gold is over here

  • and is close to these but is not normally considered a platinum group metal

  • Noble is an old-fashioned word meaning it doesn't react

  • a posh way of saying, "chemically boring."

  • The noble gases--they didn't think reacted with anything.

  • Now they know some of them do, but noble is

  • dismissing them as being worthy but boring

  • The important thing about the noble metals, the platinum group metals

  • is they're fantastic catalysts

  • they can be used for all sorts of applications,

  • making nitric acid, cleaning up car exhaust

  • and many other applications

  • So of course, in all this processing, they generate dust.

  • And most of it is caught, but some of it you can't avoid going into the air and falling to the floors .

  • So some of it collects on our shoes

  • So when you go in and out, they have special brushes

  • to clean the bottom of your shoes, and they recover really quite a large amount of metal

  • each year, worth more than a decent sized car

  • What they're doing in this factory

  • is taking this material, which is called sponge

  • which is what comes

  • from the mines. This is platinum sponge here

  • and in this bottle here is rhodium sponge

  • and it's much finer because rhodium is the last element to come out of the process

  • in the mines.

  • So they take this sponge

  • and turn it into grains, rather like this.

  • Here are grains of platinum

  • this is probably the only time in my life

  • that I will be able to play with platinum in such a casual way

  • and over here--I'll use the other hand so I don't mix them up--

  • are similar sorts of grains of iridium.

  • but they're very much heavier.

  • They turn this sponge

  • into those grains

  • by heating it up to high temperature

  • melting it, and then pouring the molten liquid out

  • and it's fantastic, you see this liquid that's so hot, it's bright red

  • and then it's cooled down rapidly to form the grains

  • and then the grains can be taken and melted

  • and cast into ingots

  • a large lump

  • and here we have an ingot of platinum

  • This weights 13 kilos

  • and you can see I can't lift it up with one hand

  • with two hands I can just about start lifting it

  • The difference between this and gold

  • is that you can use platinum as a catalyst

  • for all sorts of chemical processes

  • so ingots like this are then turned into bars like so

  • first of all by hammering the ingot very hard

  • with a heavy hammer when it's really hot

  • And the fantastic thing is at it hammers it, the metal gets hotter

  • the energy of the hammer is turned into heat

  • it starts glowing redder and redder

  • and then they take the hammered bar

  • and draw it down through a series of dies

  • so it first of all gets into a coil like this

  • and as the coil comes out of the die

  • it coils itself up. It's almost like magic,

  • you see this coming out and going round and round and round

  • I was mesmerized.

  • And then they take this heavier bar and put it through a series of dies

  • 'til in some processes it gets narrower than my hair.

  • I didn't actually take out a hair to measure,

  • but I believe them.

  • And I couldn't see it, easily. The braider is much better with his lens and saw it.

  • Once they've got these fibers, these wires, they can then start making all sorts of materials.

  • They can knit the fibers together

  • or weave them, just like you do with cloth

  • to make fine meshes, which are used in the chemical industry

  • for catalyzing reactions.

  • Particularly, for example, turning ammonia into nitric acid

  • This process that we've all read about in books

  • ammonia going into nitric acid, but actually to see

  • these huge pieces of fiber woven together,

  • and what's so interesting is that they're so thin

  • You imagine, when you see a huge chemical plant,

  • that it's full of catalysts, whereas in fact the operating catalyst

  • is really quite thin, and the reaction takes place very fast

  • and you need the rest to warm it up and cool it down afterwards

  • It's important to stress that in the mines

  • for the platinum group metals, and the main mines are in South Africa

  • in Russia, some are in Zimbabwe, and some are in Canada

  • in all these places, the amount of platinum group metals in the rock

  • is very very small

  • to make an ounce of this sponge

  • you require somewhere between 10 and 40 tons of rock.

  • A huge amount. And the other thing, the processing is not instantaneous,

  • once you've got the rocks out, to get the platinum material,

  • takes about six weeks of processing, letting things settle, processing some more

  • and rhodium takes another fourteen weeks, so twenty weeks, nearly half a year

  • to get the rhodium once you've dug the rocks to this stage

  • but once it gets here, they can process things really quite quickly.

  • Some of the samples we saw when we arrived

  • are already being processed.

  • Had to get us another ingot of platinum, the one we saw has already gone into the factory.

  • 94% platinum, 6% rhodium, and part of the reason for this is that rhodium is a much rarer element

  • and also that people have found platinum, with a bit of rhodium

  • gives particularly good...

It's quite difficult to get into places like this. You have to remove everything metallic. I'm not even wearing a belt.

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超級昂貴的金屬 - 視頻週期表 (Super Expensive Metals - Periodic Table of Videos)

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    林宜悉 發佈於 2021 年 01 月 14 日
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