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Earth Science

Hierarchical Membrane For Cleaning Up Oil Spills 32

rtoz (2530056) writes Whenever there is a major spill of oil into water, the two tend to mix into a suspension of tiny droplets, called an "emulsion." It is extremely hard to separate them, and they can cause severe damage to ecosystems. Now, MIT researchers have discovered a new, inexpensive way of getting the two fluids apart again. This new approach uses membranes with hierarchical pore structures. The membranes combine a very thin layer of nanopores with a thicker layer of micropores to limit the passage of unwanted material while providing strength sufficient to withstand high pressure and throughput.
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Hierarchical Membrane For Cleaning Up Oil Spills

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  • Solved problem (Score:5, Insightful)

    by snsh ( 968808 ) on Wednesday July 02, 2014 @11:08AM (#47368795)

    Easier to follow Exxon's example and dump tons of dispersant into your oil spill, and watch the globs disappear from plain sight.

    • by pepty ( 1976012 ) on Wednesday July 02, 2014 @11:29AM (#47368969)
      You know, I don't think I've ever heard of a mix of cash, lawyers, and lobbyists being referred to as "dispersant" before.
    • Re:Solved problem (Score:4, Insightful)

      by frinkster ( 149158 ) on Wednesday July 02, 2014 @11:46AM (#47369123)

      Easier to follow Exxon's example and dump tons of dispersant into your oil spill, and watch the globs disappear from plain sight.

      How this got moderated as Interesting I have no idea - I found it to be quite funny.

      But the truth is that that industrial corporations are very sensitive to economics. Crude oil is very valuable and dispersant is very expensive. Any product that allows them to recover the oil economically will be used extensively.

      The environmental movement really advanced when people started explaining to corporations that pollution was nothing more than raw inputs that they paid for and are now throwing away. A lot of industrial companies have entire divisions dedicated to selling products produced with what used to be stuff they threw out or paid someone to dispose of.

      • Re:Solved problem (Score:4, Informative)

        by i kan reed ( 749298 ) on Wednesday July 02, 2014 @12:11PM (#47369357) Homepage Journal

        BP got in big trouble for an internal memo that discussed the idea of reclaiming the oil. It was a "how dare they think of protecting their assets after doing this" outrage.

        I don't have a strong opinion about that memo or the outrage(even though I'm quite concerned with environmental matters on principle). Just that that happened.

      • Perhaps. Economically is the key word though, and that filter is going to have to be phenomenally cheap and effective to make it worth it for recovering oil from seawater. How many barrels of oil at $100 per barrel do you suppose $100 worth of filter can filter out? And then you have the fact that the filtered oil is going to be thoroughly contaminated with salts, plankton, diatoms, and everything else found in seawater that's either oil soluble or bigger than an oil molecule, which could potentially inc

  • by pepty ( 1976012 ) on Wednesday July 02, 2014 @11:17AM (#47368859)

    Solomon performed experiments showing the effectiveness of the membranes in separating nanoemulsions while maintaining integrity at high pressure. The team used various techniques — including differential scanning calorimetry, dynamic light scattering, and microscopy — to test the separation efficiency, showing more than 99.9 percent separation. Microscopy images show the membrane in operation, with dye added to the water to make the droplets more obvious. Within seconds, an oil-water mixture that is heavily clouded becomes perfectly clear, as the water passes through the membrane, leaving pure oil behind. As shown in the microscope images, Solomon says, “We’re not only getting rid of the droplets you can see, but also smaller ones,” which contribute to the cloudy appearance.

    How much oil (weight/weight) can a piece of membrane hold on to? Can the oil be stripped off of the membrane so that the membrane can be reused? If the answers are "less than 1:1" and "no", this might still be useful as a final purification stage after most of the oil has been removed or for situations where you are trying to clear smaller amounts of more toxic materials.

    • I was under the impression that the membrane was simply separating oil from water, but not holding onto anything. A mechanical process could simply wipe the oil from the membrane, while at the same time apply pressure to push the water through.

  • Kevin Costner had a centrifugal separator that was highly efficient, but could not achieve clean enough water to be allowed to help with past oil spills. Mixing his system with this could get the total system efficiency needed to do significant recovery of spilled oil.

  • Mayonnaise is also one of earth's nastiest substances - it's like the love-child of white phosphorous, Ebola, and that "Leave Brittany Alone" emo guy.

    Mayonnaise is also an emulsion. Now my plans can begin in earnest.

    • by mi ( 197448 )

      Mayonnaise is also one of earth's nastiest substances

      This is only true about factory-made mayonnaise. The original recipe is drastically different — but can not be stored for more than a few days. If you are willing to deal with such quickly-expiring product, you can make your own at home. Recipes abound [].

    • by Bengie ( 1121981 )
      Emulsion of oil(stuff I buy uses virgin olive oil), vinegar, egg yolk, and salt. I'm not quite sure how this is "nasty".
      • Emulsion of oil(stuff I buy uses virgin olive oil), vinegar, egg yolk, and salt. I'm not quite sure how this is "nasty".

        I guess you'd need to watch the movie Undercover Brother. Its mayonnaise scene scarred me for life.

        And, the idea of uncooked egg still creeps me out, to be honest.

  • The Demon [] would guard a door letting fast-moving molecules of some gas (or liquid) through, but blocking the slow-moving ones. Thermodynamics will never be the same!

  • by Anonymous Coward

    Wasn't this issue already solved, there was I believe some competition a few years back after the gulf spill where several designs competed for prize money. One using a simple rig with rotating plastic disks with groves in them blew away the competition and went FAR beyond the requirements of the competition. Sounds like a lot easier & cheaper solution then some kind of nano material.

    • by tomhath ( 637240 )

      Here's a better discussion of skimmers []. They certainly have their place and the Elastec design is very efficient.

      Skimmers work on a film of oil floating on the surface, not so much for oil that has already gone into suspension under the water. This filter seems to fit the latter scenario better

    • by 517714 ( 762276 )
      Technically, yes, there are solutions. Politically, no, the Federal Government would not allow BP to deploy booms and skimmers that, being under foreign registries, might not be unionized. In hindsight, BP should have used them and appealed to Congress, the courts, and the American people for relief from the Executive Department's overreach.
  • They will no longer need to worry about oil spills. Many of those silly, and very expensive 'safety' precautions can now be avoided. Saving costs increases shareholder value.

    The only real drawback to this solution seems to be that the membrane's ingredients do not include ground up kittens and babies.
  • Left alone these problems have been vanishing according to recent reports. Nature is eating it up. I'm not suggesting spilling more oil, far from it, but rather to not panic quite so much.

  • I read about this and I wish them well, especially when the membranes start to clog-up with real-ocean dirt and bacteria move in to build a cozy biofilm community.
  • Now all we have to do is cover the sea floor with this carpet and lift it up whenever there's a need. Perfect!

Experience varies directly with equipment ruined.