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Repurposed: Ground Circuit Board Waste Can Clean Up Toxic Metals

ckwu writes "Researchers in Hong Kong have found a beneficial new use for the electronic waste from discarded cell phones, computers, and other gadgets. Ground up into a powder, printed circuit boards from these products could sponge up another type of pollution — toxic heavy metals in water. The researchers processed the nonmetallic fraction of waste circuit boards into a powder and found that it adsorbed metals like copper, lead, and zinc more efficiently than commercially available industrial adsorbents."

33 comments

  1. "china" by Anonymous Coward · · Score: 0

    necessity is the mother of all design

    1. Re:"china" by Anonymous Coward · · Score: 0

      There's easier way, just burn more coal and the fog will hide the toxic heavy metals in water from view.

  2. That's the clever part, by Kaenneth · · Score: 4, Funny

    When Winter comes, the Gorillas will all freeze to death.

    1. Re:That's the clever part, by HairyNevus · · Score: 4, Informative
      For those scratching their heads:

      Skinner: ahh, but as it turns out the lizards where a god send since they've eaten all the pigeons.
      Lisa: Isn't that a little short sighted, what happens when where up to our ears with lizards?
      Skinner: Ah, well we shall simply release wave after wave of Chinese needles snakes.
      Lisa: then what about the snakes?
      Skinner: We simply import gorillas who will eat all the snakes.
      Lisa: Well what happens when we're up to our ears in gorilla's!
      Skinner: Ah that's the beauty of the thing, come winter the gorillas will freeze to death.

      --
      You were critically hit for no damage. The bruise will look nice, and maybe the scars will make good party talk.
    2. Re:That's the clever part, by Anonymous Coward · · Score: 0

      I didn't know this dialogue but it wasn't necessary anyway, your parent was clear enough :-))

    3. Re:That's the clever part, by Anonymous Coward · · Score: 0

      In the end the Starks are always right

  3. Luddites by Anonymous Coward · · Score: 0

    Don't they know that makers equipped with the latest in 3D printers will render PCBs obsolete?

    1. Re:Luddites by Em+Adespoton · · Score: 1

      Don't they know that makers equipped with the latest in 3D printers will render PCBs obsolete?

      These guys are already rending PCBs, so they probably don't care....

  4. Ground Up Fiberglass by Anonymous Coward · · Score: 0

    Sounds like an environmental solution that could only come from China.

  5. Re:Reduce, Reuse, Recycle ? by Gaygirlie · · Score: 1

    If you'd care to read TFA you'd notice that they aren't grinding up the whole thing, they are just grinding up the board, ie. non-metallic components. The metallic components are retrieved and recycled. As such your rant is completely misplaced.

  6. good tech doing good work by kermidge · · Score: 4, Interesting

    This is good tech stuff, for real-world use and valid "news for nerds, stuff that matters" - oops, we don't do that here anymore. It's one of the ways tech is supposed to work.

    Somebody had a thought, "I wonder..." or "What if..." and tested it.
    It worked; in fact, it worked very well. The need is not restricted to China, either.

    What's not to like? Where's the applause?

    1. Re:good tech doing good work by slew · · Score: 3, Informative

      FWIW, it's not as if non-metallic recycled parts of circuit boards aren't in wide use today.

      The groundup non-metalic parts of circuit boards are used in plastic lumber, insulating concrete, asphault, and as a structural filler for some composite materials which are used for various types of products from furniture, to lunch trays and picture frames. Generally this pcb-waste-resin composite material is considered a high-quality replacement for wood-plastic material resulting in material that handle better bending stresses.

      The use of this in pulverized power form after treatment with KOH as heavy metal adsorber/filter is perhaps interesting/novel, but as stated in the article...

      Although the boards can become effective adsorbents, he says the method for making the materials may not be as energy efficient and cost effective as for other adsorbents, such as granular ferric hydroxide, because of all the processing steps needed to produce the treated powder.

      And since there are many other current uses for the waste circuit board material that require less energy and processing steps, it's not clear that this result is anything other than a novelty result...

    2. Re:good tech doing good work by Catiline · · Score: 1

      I think here people are waiting for the "The circle is now complete.... once I was e-waste now I am the cleaner product." jokes.

    3. Re:good tech doing good work by kermidge · · Score: 1

      Thanks for the clarification and info on other, more energy-efficient uses for the material - I hadn't thought to look into it - my bad. I like the way that people are finding more ways to use things that otherwise would be sent to the dump. (I recall from the late 70's a push to look into ways to scavenge and re-use stuff for fun and profit, and it looks like that mindset is paying off.)

    4. Re:good tech doing good work by kermidge · · Score: 1

      Ah, yes; I think to draw the line at using cremains for making stronger concrete, tho. Then again, when I'm done with my bod and whatever use the medical folks can get from it, it might make sense for the remains to end up in a highway bridge or something - might as well get some use for the stuff rather than getting buried in the ground or sitting in an urn on some shelf. Another possibility might be as part of compost.

  7. Re:Reduce, Reuse, Recycle ? by Anonymous Coward · · Score: 0

    If one has "laptop dust", which consists of plastic, rare earths, lead, and various other sundries, it definitely isn't as easy to recycle as taking an aluminum keg to a scrapyard and remelting it.

    The epoxy for the circuit board would have to be dispensed of, likely via thermal depolymerization, so you are left with short petroleum chains to filter out. Then, it will take a lot of work to separate out the yttrium, lead, tin, gold, silver, and other items. Likely too much to bother reclaiming what was present.

  8. Lead free solder? by viperidaenz · · Score: 1

    Too bad if the old PCB's don't use lead free solder. They're already covered in the copper they're trying to absorb.

    1. Re:Lead free solder? by iksbob · · Score: 1

      Not even reading the summary, now? It says right there "the nonmetallic fraction of waste circuit boards". So were talking about a ground-up mixture of fiberglas and epoxy resin here.

    2. Re:Lead free solder? by viperidaenz · · Score: 1

      or paper and glue.
      Not all PCBs are FR4. The cheap crap from China is phenolic.

  9. Costs more to do less = Dead at the start by loose+electron · · Score: 1

    From the article:

      Although the boards can become effective adsorbents, he says the method for making the materials may not be as energy efficient and cost effective as for other adsorbents, such as granular ferric hydroxide, because of all the processing steps needed to produce the treated powder.

    Conclusion - its dead before its even starts.

    --
    www.effectiveelectrons.com "chips that work" Analog, RF, Mixed Signal
    1. Re:Costs more to do less = Dead at the start by Beorytis · · Score: 2

      From the article:

      ...method for making the materials may not be as energy efficient and cost effective as for other adsorbents...

      Conclusion - its dead before its even starts.

      Right, because no one has ever figured out how to make a chemical process more energy efficient or cost effective before.

  10. Now what by the+eric+conspiracy · · Score: 1

    Ok, so now I have ground up circuit board contaminated with heavy metals.

    What can I do with this? Sell it to China for incorporation into dog food and baby formula?

  11. That's crazy talk by Iniamyen · · Score: 1

    Next thing you know the Chinese will be using petroleum products to clean up oil spills. Crazy Asians.

    1. Re:That's crazy talk by slew · · Score: 1

      Next thing you know the Brits will be using petroleum products to clean up oil spills. Crazy Brits.

      FTFY...

    2. Re:That's crazy talk by Anonymous Coward · · Score: 0

      whoosh

  12. Powdered mix? by Anonymous Coward · · Score: 0

    Hopefully they're not eyeing the infant formula market with this special blend.

  13. nonmetalic pcbs? by gnu-sucks · · Score: 1

    "The researchers processed the nonmetallic fraction of waste circuit boards into a powder and found that it adsorbed metals like copper, lead, and zinc"

    I'm not going to read the article (I am a slashdot user after all), but where in the world of electronic waste do you find PCBs without any metal? That would mean they don't have any traces or solder joints... unlikely to say the least.

    1. Re:nonmetalic pcbs? by Ignacio · · Score: 2

      Either as wire-wrap perfboards, or you heat up 2-layer PCBs (to burn out the adhesive holding down the traces) and strip out the vias.

    2. Re:nonmetalic pcbs? by erice · · Score: 1

      "The researchers processed the nonmetallic fraction of waste circuit boards into a powder and found that it adsorbed metals like copper, lead, and zinc"

      I'm not going to read the article (I am a slashdot user after all), but where in the world of electronic waste do you find PCBs without any metal? That would mean they don't have any traces or solder joints... unlikely to say the least.

      Two layer PCB's with the surface metal already stripped off. More likely left over material when odd shaped PC boards were cut from rectangular sheets.

    3. Re:nonmetalic pcbs? by Anonymous Coward · · Score: 0

      The point is that you recycle the pcb-s anyway to get the costly parts out - that is the metals. What you are left with once you have taken everything out is mush of epoxy and fiberglass. So far this "nonmetallic fraction" has been a useless leftover. Now they found a use for it. Seems like a useful discovery to me.

  14. Re:Reduce, Reuse, Recycle ? by gnu-sucks · · Score: 1

    Forgive me, but what part of a printed circuit board is metal-free? The edge? Certainly not 99.9% of it.

  15. Re:Reduce, Reuse, Recycle ? by Anonymous Coward · · Score: 0

    70% of it, according to the study. http://pubs.acs.org/doi/abs/10.1021/es4001664?source=cen