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Recycling Reality: Humans Set to Trash Most Elements on the Periodic Table

The views expressed are those of the author and are not necessarily those of Scientific American.


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Almost all lead is recycled, among the only elements on the periodic table to earn that distinction. With good reason, mind you: the soft metal is a potent neurotoxic known to impact children’s brain development, among other nasty health effects. Today, nearly all lead is used in batteries (though it was once put into gasoline, leading to widespread contamination, and, in places like Afghanistan, still is.) Most of this dangerous element is now endlessly cycled from battery to battery, thanks to stringent regulations (though enough of it ends up being improperly recycled to constitute one of the world’s worst pollution problems.)

In principle, all metals are infinitely recycleable and could exist in a closed loop system, note the authors of a survey of the metals recycling field published in Science on August 10. There’s a benefit too, because recycling is typically more energy-efficient than mining and refining raw ore for virgin materials. Estimates vary but mining and refining can require as much as 20 times the amount of energy as recycling a given material. Think about it: a vast amount of energy, technology, human labor and time are expended to get various elements out of the ground—and then that element is often discarded after a single use.

metal-cycle

Lead is not alone in being recycled, of course. Aluminum, copper, nickel, steel and zinc all boast recycling rates above 50 percent (though not much above 50 percent). The same principles can be usefully applied to other materials, like plastics. After all, these ubiquitous polymers are made from another scarce resource—oil—and many are, in principle, recycleable. Yet, the overall recycling rate for plastics, grouped as a whole, is only 8 percent (as of 2010, per EPA numbers.) Take the case of polypropylene (or #5 plastic if you’re checking the bottom of your food containers). The bulk of this polymer that gets recycled comes from car batteries. It is, in essence, tagging along with the lead. In other cases—water bottles, yogurt cups, you name it—it simply disappears into the nation’s landfills.

Meanwhile, the majority of elements on the periodic table—and we use almost every element on the periodic table for something or other—are also nearly completely unrecycled.

As an example, industrial ecologists Barbara Reck and T.E. Graedel of Yale University compare the fates of nickel versus neodymium. Nickel is ubiquitous, particularly as an alloy for steel. Of the 650,000 metric tons of the silvery-white metal that reached the end of its useful life in one product in 2005, roughly two-thirds were recycled. And that recycled nickel then supplied about one-third of the demand for new nickel-containing products. That means the overall efficiency of human use of nickel approaches 52 percent. Not bad, but there’s room for improvement, given that almost half of all nickel is only used once before it is discarded.

Nearly 16,000 metric tons of neodymium—a so-called rare earth metal—were employed in 2007, mostly for permanent magnets in everything from hybrid cars to wind turbines. Roughly 1,000 metric tons of the element reached the end of its useful life in one product or another—and “little to none of that material is currently being recycled,” the survey authors note. This despite the fact that a “rare earth crisis” stems from China’s near monopoly of the neodymium trade.

Mining for neodymium is not benign (which is why the world lets China monopolize its production). And it’s not just neodymium. Mining waste—or tailings, leach ponds, slurries and the like—are among the world’s largest chronic waste problems. North America alone produces 10 times as much mining waste as it does the municipal solid waste (as it’s known) from all the neighborhoods in the U.S. Much of that is just rock, sand and dust—the mountaintop in mountaintop removal mining. And mined products also cause waste further down the product line, such as the ash leftover after the coal is burned (the U.S.’s largest single form of waste).

This issue of profligate use gets worse: we are currently making this problem even harder to solve. How? One word: gadgets. In most gadgets you can think of, tiny amounts of rare elements are used to enhance functionality. As the industrial ecologists write in Science: “The more intricate the product and the more diverse the materials set it uses, the better it is likely to perform, but the more difficult it is to recycle so as to preserve the resources that were essential to making it work in the first place.” It’s as true of iPhones as it is of photovoltaic panels—and none of them have shown much success in being recycled. “End of life losses will also increase sharply soon,” unless something changes, the industrial ecologists warn.

Then there are the alloys, where thermodynamics dictate that the alloying element is almost always going to be lost due to the difficulty of separation. That means the chromium used in stainless steel will usually lose its luster, for example. Worse, this form of contamination can mean that the recycled alloy can’t be re-used—manganese-aluminum alloys are unsuitable once recycled for 95 percent of the uses for aluminum. As a result, “current designs are actually less recycleable than was the case a few decades ago,” the authors note. Perhaps the use of such metal combinations should be minimized?

In the end, our approach to recycling is bizarre, given our resources. “Few approaches could be more unsustainable,” Reck and Graedel write. In the end, we’ll learn to reuse all the elements of the periodic table, or we’ll lose elements to use.

Image courtesy of Barbara Reck, based on Reck et al. (2008), Env. Sci. & Tech.

About the Author: David Biello is the associate editor for environment and energy at Scientific American. Follow on Twitter @dbiello.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. priddseren 12:22 am 08/10/2012

    The problem is everyone is trying to force the recycling to begin with the consumer or user of the product to avoid the hassle of having to do the separation at the garbage dump. There is no feasible way to get every person to separate every metal or plastic they use for recycling. For obvious reasons, like contamination, we cant have everyone smashing up their old cell phone and trying to extract the component metals and raw materials to then place in the appropriate bin.

    So what do you do about it? Simple, have everything sent to the dump and start mining the materials out of the dump. Do the separation there, set up facilities to get these metals and plastics from various devices. It doesn’t cost more, because you cant do it at the residence anyway for anything other than large objects made of one basic material.

    So start mining the dumps and get the recycling to 100%.

    Link to this
  2. 2. Ralf123 1:02 am 08/10/2012

    >There is no feasible way to get every person to separate every metal or plastic they use for recycling

    Probably, but it’s easy to achieve significant recycling ratios: Make a law, create the necessary infrastructure, and put a high enough deposit on everything.

    Link to this
  3. 3. ManOfPhysics 10:26 am 08/10/2012

    I hope to retire by investing in the businesses that are focused on “mining” dumps and by buying up the land “mineral rights” where former dumps used to be!

    Link to this
  4. 4. geowiz875 12:10 pm 08/10/2012

    I recently bought a new mobile phone in Australia (WA) and in the packaging was a little plastic bag which was a prepaid parcel post. You put your old phone and charger in, seal, and pop in a mailbox addressed to an eastern state address 4000 km away. I presume the destination is a specialized recycling facility for old handphones.
    Neat, huh!

    Link to this
  5. 5. jack.123 6:50 pm 08/10/2012

    This is why we need to get to the asteroids now!Certain billionaires know this and are on their way to them by building the technology needed to get there.Nasa needs to give them all the help it can.The nations that get on this bandwagon will be the superpowers of tomorrow.These missions will not only provide elements for Earth,but would provide materials for spaced based manufacturing that would eliminate the need to put them in orbit.The next generations of interplanetary spacecraft could be built entirely in space without the need for returning to Earth.This would save untold amounts of money.

    Link to this
  6. 6. Heteromeles 4:11 pm 08/16/2012

    So instead of biogeochemistry, we really need to have specialists in “anthropobiogeochemistry.”

    The bigger problem with trash is that it’s so easy to contaminate recycling streams. A few batteries is enough to poison an industrial sized compost pile, for example, as well as enough to turn sewage into industrial waste. The real problem is how to idiot-proof recycling, since idiocy is not a limited resource. This may sound silly, but it’s the biggest problem faced by all waste managers today.

    Link to this

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