One of the things I've learned via my reading about cosmology is why some elements are so rare. Just after the big bang, the universe was so dense and hot that there were just particles, not elements. At 380,000 years old, the universe cooled and Hydrogen formed. As gravity forced clumping of H, stars were formed and ignited with nuclear fusion and fused H together to make Helium. As the H burns off if there's enough mass and therefore gravity to keep the He dense it might ignite and form other elements. Though various stellar nucleosynthesis processes all the elements up to Iron (element 26) can form (including carbon, oxygen, nitrogen, etc.) Every element higher than 26 (including gold, silver, copper, tin, etc.) all formed in the heat of supernovas. That's why these elements are so rare on earth. After supernovae send these elements out into space, the next generation of stars and planets form. I've often heard this described as "we are stardust". All of the atoms that make you and our world came from previous generations of stars and supernovae.
Sci-Fi writer Robert Silverberg writes Reflections: The Death of Gallium. "But now comes word that it isn’t just wildlife that can go extinct. The element gallium is in very short supply and the world may well run out of it in just a few years. Indium is threatened too, says Armin Reller, a materials chemist at Germany’s University of Augsburg. He estimates that our planet’s stock of indium will last no more than another decade. All the hafnium will be gone by 2017 also, and another twenty years will see the extinction of zinc. Even copper is an endangered item, since worldwide demand for it is likely to exceed available supplies by the end of the present century."
Silverberg goes on to describe how Gallium is used to make LCDs and Hafnium and Indium are used to make computer chips. A World Without Zinc (sorry no youtube link) could come to pass.
If you want more details read David Cohen's article in the New Scientist, Earth's natural wealth: an audit.. "Platinum is a vital component not only of catalytic converters but also of fuel cells - and supplies are running out. It has been estimated that if all the 500 million vehicles in use today were re-equipped with fuel cells, operating losses would mean that all the world's sources of platinum would be exhausted within 15 years. Unlike with oil or diamonds, there is no synthetic alternative: platinum is a chemical element, and once we have used it all there is no way on earth of getting any more."
"So what can be done? Reller is unequivocal: "We need to minimise waste, find substitutes where possible, and recycle the rest." Prichard, working with Lynne Macaskie at the University of Birmingham in the UK, has found that platinum makes up as much as 1.5 parts per million of roadside dust. They are now seeking out the largest of these urban platinum deposits, and Macaskie is developing a bacterial process that will efficiently extract the platinum from the dust."
7 comments:
Starch said:
Sorry I just don't buy it. Non-radioactive materials don't go away they just change hands. 90%+ of the steel used today is recycled. Because it's cheaper to recycle than create more.
Prices may climb and fall due to supply and demand, but the volume is always there
The interesting dynamic is that businesses are profit driven, so companies pay engineers to replace expensive materials with cheaper alternatives. Even now there are engineers across the row form me is working on making atomic micro-layered magnetic materials for HDDs with less expensive metals, with the same performance. Because there’s a lot of precious metal in the 5,000,000 HDDs shipped each week.
We can do better recycling exotic materials from end of life devices, instead of shipping this “waste” to China, but right now it’s cheaper to scrap them.
I buy that. But I could believe there isn't enough gallium to give everyone an LCD (or two or three). Yes there's recycling, and I'm sure we'll do more, but it must be pretty bad if people are thinking of getting Platinum from roadside dirt.
Start replies:
I'd be very surprised if gallium is required to build an LCD. I would bet gallium is the cheapest solution, and people are worried about their profit margins next year.
As for Pt being pulled out of the ground, that's where it comes from. I think America still has a lot of natural resources, but the land value is to high to claim it so we buy it elsewhere. I can't imagine strip mining Tahoe for gold, when each acre of land sells for $1,000,000 for recreational use.
For the Pt I was referring to the beginning of the last article I linked to: ""I GET excited every time I see a street cleaner," says Hazel Prichard. It's what they collect in their sacks that gets her juices flowing, because the grime and litter they sweep up off the streets is laced with traces of platinum, one of the world's rarest and most expensive metals. The catalytic converters that keep exhaust pollutants from cars, trucks and buses down to an acceptable level all use platinum, and over the years it is slowly but steadily lost through these vehicles' exhaust pipes. Prichard, a geologist at the University of Cardiff in the UK, reckons that tonnes of the stuff is being sprayed out onto the world's streets and highways every year, and she is hunting for places where it is concentrated enough to be worth recovering. One of her prime targets is the waste containers in road-sweeping machines."
Starch:
Catalytic converters are another tech that confound me. The last breaktrough I've heard about was in 1981 (26 years back), which just became required in 2007.
http://en.wikipedia.org/wiki/Catalytic_converter
I'd bet a dinner that all the R&D spending on converters is focused on making them cheaper (diluting Pt) because the marketing guys in D.C. have the emissions laws covered.
I agree with anon(2). Gallium is a way to make semiconductors but if it becomes too expensive then people move on to other solutions.
There are organic solutions coming for some of the uses of these metals. A lot of them require metal for catalysis but I have to imagine that as prices go up the market will find substitutes or what was once waste will become resource as it becomes worth it to recover the material.
You two probably know each other. :)
I understand that for most uses alternatives can be found. I wonder what (stable) elements we've run out of?
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