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Scientists Turn Paper Waste Into Aerogel (inhabitat.com)

Posted by yaelk on from the conservation-news dept.

Kristine Lofgren writes: A team of scientists have successfully turned paper waste into aerogel. Aerogels are used in insulation, and they are usually made out of polymers and silica. But a research team at the National University of Singapore managed to make the highly sought-after product using recycled paper, which could have huge implications not only for the rate at which we are filling up our landfills, but also for the amount of chemicals that we are producing and releasing into the environment.

37 of 54 comments (clear)

  1. fire! by blogagog · · Score: 2

    It seems like it would be difficult to make a mostly paper product flame retardant.

    1. Re:fire! by rmdingler · · Score: 1

      It seems like it would be difficult to make a mostly paper product flame retardant.

      Well sure, but for those of you /. posters who routinely work Mission Impossible, the very difficult is rather mundane.

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    2. Re:fire! by Fly+Swatter · · Score: 4, Informative

      Recycled paper is already used to make cellulose insulation, and has been for many years. By necessity it is full of flame retardants. It is nothing new.

      The actual article only mentions insulation in passing, in the picture it looks more like a standard foam product. Nothing like cellulose insulation. They hope to initially use it for cleaning up oil spills.

    3. Re:fire! by choprboy · · Score: 2

      It seems like it would be difficult to make a mostly paper product flame retardant.

      Actually it is quite easy. Finely shredded paper is commonly used as a high-R value blown-in insulation for attics and wall cavities. The paper is treated with boric acid which acts as a flame retardant.

    4. Re:fire! by del_diablo · · Score: 2

      Aerogel is solid smoke, or solid gas, per definition. Or at the least thats the wikipedia simplified explanation.
      So paper contains chemicals that can be used to make one form of solid smoke.
      Now here is the important thing about Aerogel: All forms of it has different properties, outside of being extremely insulating, and extremely non dense(light), and usually quite hard. Further properties depend on what its made from.
      Some are super fragile, some can bend, etc.

    5. Re:fire! by Harlequin80 · · Score: 4, Informative

      Nope, very easy in fact. Shredded paper is one of the best roof insulations you can get and it is treated with boric acid to make it fire retardant. Here is a link to someone hitting Cool or Cosy (a brand name version of shredded paper insulation) with a blow torch.

      https://www.youtube.com/watch?...

    6. Re:fire! by dsmatthews9379 · · Score: 1

      Boron, moron.

    7. Re:fire! by Rei · · Score: 1

      Huh? You want to trap hydrogen in an open cell substance?

      --
      We should start dealing in those black-market beagles.
    8. Re:fire! by Rei · · Score: 1

      Aerogel is of course nothing at all like loose-fill cellulose insulation. But no, it should not pose a fire risk either. Depending on the type, aerogels are generally considered either fire retardant or non-flammable; even if they're made of something that "burns" on a macroscopic level, there's so little "something" there to burn that the flame barrier properties that they provide generally well outweighs the heat output of their own combustion.

      --
      We should start dealing in those black-market beagles.
    9. Re:fire! by Rei · · Score: 1

      Because nobody doesn't like molten boron!

      --
      We should start dealing in those black-market beagles.
    10. Re:fire! by ledow · · Score: 1

      Try and light a matchbox.

    11. Re:fire! by Impy+the+Impiuos+Imp · · Score: 1

      I would have thought it evplosive, like coal or corn dust, well distributed thru a volume of air.

      --
      (-1: Post disagrees with my already-settled worldview) is not a valid mod option.
    12. Re:fire! by Immerman · · Score: 1

      Has anyone actually managed to create a "vacuum-filled" aerogel? My understanding was that they were typically open-celled structures created by replacing the water in a gel with air. Though I suppose if the strength was sufficient you could encase it in an airtight skin and then pump out the air. That might have applications for rigid lighter-than-air craft, or as even more effective insulation. At least until a few days after a pinprick forms somewhere in the skin.

      Of course the air can then be replaced by something else quite rapidly, giving them impressive absorption properties. Essentially they're an extremely low-mass sponge.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    13. Re:fire! by Creepy · · Score: 1

      The 1960s era insulation in my attic is exactly that - shredded newspaper treated with fire retardant. The main problem with it is that it tends to settle more than fiberglass and apparently doesn't insulate as well after it settles. Mine had dropped a good 6" (15cm) when I had additional fiberglass insulation blown in.

    14. Re:fire! by Immerman · · Score: 3, Interesting

      I would have thought similarly, but Wikipedia says otherwise (https://en.wikipedia.org/wiki/Aerogel). Perhaps a flame-front can't advance fast enough through a rigid structure?

      Heat cannot spread through aerogels quickly, nor can the expanding hot air front spread further into the fuel, so I'm guessing only the outermost surface can be thermally catalyzed, and thanks to their incredibly low density there's not going to be a lot of other fuel within range of a burning molecule to absorb the energy before convection carries it away from the surface.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    15. Re:fire! by Immerman · · Score: 1

      Well, that's more of a common nickname based on appearance than a definition, there's not really anything else smokelike about them except density. Calling someone a carrot-top doesn't make them a vegetable.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    16. Re:fire! by spazzmo · · Score: 1

      Yeah, I've always wondered about aerogel airships.

      Make a lot, cover with a skin that won't leak, fill from the bottom. Hydrogen gas is less leaky that helium (as He is monatomic).

      So, would the aerogel slow the rate of combustion if there was an incendiary accident at a puncture site due to there being a less of an interface with the atmospheric oxygen compared to a balloon? Well, probably not with a paper aerogel, say a silicon one.

      And how would the reaction progress through the aerogel? If it was slow enough/not fatally toxic it would make the hydrogen gas safe.

      "Attention passengers, we have a fire in the top forward gelsac, we will be landing shortly. Passengers will then disembark into inflatable life-rafts."

      Any physicists care to comment?

      --
      The cheese stands alone...
    17. Re:fire! by spazzmo · · Score: 1

      Sorry, just read further, looks like it would work, even with paper. The only question is the rate of the reaction.

      --
      The cheese stands alone...
    18. Re:fire! by Immerman · · Score: 1

      Hmm, on further though, we could fill the aerogel with hydrogen gas - that shouldn't alter the density much compared to being "vacuum filled", and would only a skin that prevented mixing, rather than preventing pressurized leaks. That would essentially eliminate the risks of leaks with even an extremely thin skin, while the aerogel would maintain a rigid airform and essentially eliminate the risk of fires. As of 2013 aerographene had been made with evacuated densities as low as 160g/m^3, compared to 1,225g/m^3 for air at STP, and 89g/m^3 for hydrogen, so you could get 976g/m^3 of lift at sea level. Not quite as good as helium, but you get the rigid airframe for free.

      The real question would be how well could it survive pressure changes - a traditional airship has to reduce it's density as it climbs to avoid over-inflating and rupturing - aerogel ships would presumably have to do the same, but depending on gel porosity that could take a lot longer to get the air our (or back in again)

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    19. Re:fire! by Immerman · · Score: 1

      Are you sure about hydrogen being less leaky that helium? I thought it was the other way around - yes, helium is monatomic, but hydrogen is a lot smaller. The result being, as best I can gather, that an H2 molecule is slightly larger than a helium atom along its long dimension, but notable smaller along its short one.

      Then again perhaps I'm thinking of hydrogen under pressure, where it will eventually pass through even solid steel tank walls. I've never heard of helium having such issues, but that could simply be because there are far fewer applications for high-pressure helium storage.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  2. heh. by Black+Parrot · · Score: 1

    A new way to deal with your rejected papers.

    --
    Sheesh, evil *and* a jerk. -- Jade
    1. Re:heh. by penguinoid · · Score: 1

      "This paper has virtually zero substance."

      0.04 g/cm^3, to be precise.

      --
      Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
  3. Re:And how does this help children? by dohzer · · Score: 1

    Yup. Children are the only things that matter.
    Screw everyone else!

  4. Re:And how does this help children? by gstoddart · · Score: 4, Funny

    Well, they could make aerogel out of children if that makes you feel better.

    Seriously? Why must every scientific advancement help children?

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    Lost at C:>. Found at C.
  5. Re:And how does this help children? by EzInKy · · Score: 1

    Children are the future, everyone else is the past.

    --
    Time is what keeps everything from happening all at once.
  6. Cheaper? by sims+2 · · Score: 2

    What I want to know is if it will be cheaper as right now even a small sample of areogel costs a small fortune.

    Its supposed to be one of the very best insulation materials but its always been extremely cost prohibitive to insulate your house with it.

    --
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    1. Re:Cheaper? by Rei · · Score: 2

      I fail to see how it's at all like composite building - it's a moulded product. Also note: frozen and freeze dried for two days. So if you want to make boats out of the stuff, you have to amortize in the cost of two days (per unit) usage of a thermally-regulated vacuum chamber large enough to put a boat in, which is a pretty expensive piece of kit.

      Also, how long is the sonication process?

      Making boats or surfboards out of the stuff sounds kind of pointless. As you already clearly know, the ideal boat hull is a twinwall composite, where you have composite layers of high tensile fabric bonded to either side of a lightweight foam or honeycomb core - the latter existing primarily to space the former out. If you replace the inner layer with aerogel, you're only cutting out the weight of the foam or honeycomb - and foams and honeycombs are already quite light. I mean, you'd save some weight... but enough to justify the cost and difficulty?

      I guess if you're going really upmarket... after all, some people buy Monster cables ;)

      --
      We should start dealing in those black-market beagles.
    2. Re:Cheaper? by whit3 · · Score: 1

      What I want to know is if it will be cheaper as right now even a small sample of areogel costs a small fortune. Its supposed to be one of the very best insulation materials but its ...cost prohibitive to insulate your house with it.

      It should be less expensive than silica aerogel (which is made of quartz, and requires elaborate drying in an autoclave-like pressure cooker). That's because freeze-drying is a cheap way to remove liquid from the voids (and you NEED LOTS OF VOIDS).

      It's unclear, however, if the mean-free-path for vapor movement is as small as a 'conventional' silica aerogel (the sample looks opaque, so probably the voids/walls are larger than wavelength of light). Silica aerogels for insulation are glass-clear (but slightly smoky) because the structure is nanometer-scale. It's unclear what cellulose does to 'improve' the product, and unclear that the product is durable.

      It's called 'biodegradable' but does that mean fungus will nibble it to nothing inside a year? Even a slow-moving variant on wood rot could quickly destroy a nanostructure. It's shown as flexible, which would be good (part of the cost of insulating a house with aerogel, is that you have to size all the house stud spacings to exactly the dimensions of factory-cut aerogel panels).

  7. Re:And how does this help children? by Anonymous Coward · · Score: 2, Funny

    I believe in making the world safe for our children, but not our children's children, because I don't think children should be having sex.

  8. Re:And how does this help children? by EzInKy · · Score: 1

    No matter what you think, children will grow up and they will have sex. By the way, meemaws have sex too Sheldon.

    --
    Time is what keeps everything from happening all at once.
  9. Re: And how does this help children? by gl4ss · · Score: 1

    basically thats all you have in singapore, doofus. singapore is all about profit.

    --
    world was created 5 seconds before this post as it is.
  10. Landfill?! by troon · · Score: 2

    could have huge implications not only for the rate at which we are filling up our landfills

    Wouldn't aerogel fill our landfills much faster than in its original, denser form?

    --
    Ydco co ,df C erb-y go. a Ekrpat t.fxrapev
    1. Re:Landfill?! by Rei · · Score: 1

      Until it crushes. Not all aerogels are strong, and in the picture we can see the guy bending it. And even the strength of "strong" aerogels is often overstated - they're high strength for their weight, but not for their volume.

      --
      We should start dealing in those black-market beagles.
    2. Re: Landfill?! by NatasRevol · · Score: 1

      paper in aerogels will do the same. Just saying.

      --
      There are two types of people in the world: Those who crave closure
    3. Re:Landfill?! by BarbaraHudson · · Score: 1

      Rats are a huge problem with landfill operations.

      --
      "Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
    4. Re:Landfill?! by spazzmo · · Score: 1

      And you can use waste gases to generate power..

      --
      The cheese stands alone...
  11. Better article by SoftwareArtist · · Score: 1

    Here's a much more detailed article:

    http://news.nus.edu.sg/press-r...

    --
    "I'm too busy to research this and form an educated opinion, but I do have time to tell everyone my uninformed opinion."