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Catalytic Carbon Extraction in Fuel Cell Production? 58

garyebickford asks: "I've been following the discussions in the media regarding fuel cells & hydrogen fuel. I have an idea (really a set of ideas) for handling the CO2 issues, which could make fuel cells a better solution. Perhaps someone who know about such things can tell me whether it's workable or not. Speculating wildly, if the carbon could be retained in the process (in a discharge tank, for instance), then it might even be useful as a feedstock for plastics, for example. How might a fuel cell process (both production and use), possibly multistage or incorporating a catalytic pre-process, emit carbon in non-gaseous form? What about a fuel cell that just converted ethanol or higher weight hydrocarbons to methanol, or perhaps a nitrite or another byproduct? Consumers could then recycle this waste to the fuel station at the next fill-up. Even this incomplete process can provide more energy per weight or volume than hydrogen, in theory. Would such a process be possible, or feasible?"
"Many fuels can be used in fuel cells, including hydrogen, methane/methanol, ethanol, and ammonia. One of the problems with all these, in fact any system that consumes hydrocarbons (either biomass or petroleum), is that at some point in the process the carbon is released as carbon dioxide. For H2 and NH3 the problem is in the production facility; for hydrocarbon fuels the fuel cell itself emits carbon in some form. Perhaps fuel cell research has tended to think in terms replacing the existing combustion model, with the given that output will be H2O and CO2. Is anyone studying the possibility of fuel cells that have other output chemistry?"
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Catalytic Carbon Extraction in Fuel Cell Production?

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  • My solution (Score:4, Interesting)

    by dex22 ( 239643 ) <> on Monday July 24, 2006 @09:39PM (#15773457) Homepage
    Build the fuel cell into a laser printer, and have it dump the carbon dust right into the toner cartridge. :)

    Do it so I can plug my computer and display into it, and power them too, and I'll buy two.
    • Re:My solution (Score:3, Informative)

      by parasonic ( 699907 )
      Toner sold today is not simple carbon dust. Toner contains carbon but is a plastic with intrinsic electrostatic properties.

      Check here [] for more info.
  • by QuantumG ( 50515 ) <> on Monday July 24, 2006 @09:43PM (#15773465) Homepage Journal
    I have a layman understanding of physics. This means I can read about advances in the field of physics and sometimes understand what is going on. This does not mean that I can propose new ways of looking at things in the field of physics. Why? Because every physicist has a layman's understanding of physics. Anything that you can come up with, they've already thought of it.

    Thankfully this doesn't happen in computer science very often. It does happen though. I remember having a long conversation with a guy who thought he had a great idea for a replacement for floppy disks (this was pre-USB). His idea was that the monitor could read the data from a device people carry around. At first I thought I misheard him. Then I calmly explained to him that monitors are output devices, not input devices. Then he asked what the difference was. Eventually he turned red and asked how you could do it. We had a discussion about flash memory and interface standards and then he got bored and went away.

    Which is typically the flow of these conversations, so excuse me for not entertaining your brilliant idea.
    • I am not a physicist, but I am a proctologist, which means I have an expert understanding of you.
    • by Spazmania ( 174582 ) on Monday July 24, 2006 @10:18PM (#15773586) Homepage
      I have a layman's understanding of architecture. That means I can't really create a correct blueprint. It doesn't preclude me coming up with a clever floorplan and asking an architect to turn it in to a usable blueprint.
      • That means I can't really create a correct blueprint.

        Neither can most architects.

        It doesn't preclude me coming up with a clever floorplan and asking an architect to turn it in to a usable blueprint.

        But that doesn't prevent him from knowing the Romans already tried that; and why we don't do it much anymore (or, conversely, why we should start doing it again. Roman radiant heating systems had a lot going for them).

        I'm not saying "don't try." I'm saying "research." It may save your architect a lot of grief.

        • It may save your architect a lot of grief.

          Meh. That's what I pay him for.

          that doesn't prevent him from knowing the Romans already tried that; and why we don't do it much anymore

          If my idea isn't workable I want him to do a good enough job explaining why not that I can make a rational choice about whether to rework the idea or abandon it and start fresh. I'm not asking him to make that choice; I'm asking for enough information so that I can make that choice.

          Certainly I'll be better off for the experience. And
          • Meh. That's what I pay him for.

            I hope he's on salary, otherwise he may have justification for not agreeing with that.

            . . .once in a while the architect will encounter a novel idea that he wouldn't have considered simply because that isn't the way its done.

            Have you looked at modern buildings? This is not their problem.

            . . .the rate of the passage of time is not a constant!

            And I'm prepared to offer you an explanation of why, but if you don't have a foundation in High School algebra first I'm going to have to
            • the rate of the passage of time is not a constant!

              And I'm prepared to offer you an explanation of why, but if you don't have a foundation in High School algebra first I'm going to have to ask you to sign up for classes, because it's going to take an inordinate amount of my time otherwise.

              "The rate of time varies in according to an equation versus the constant speed of light. It gradually changes such that you can never quite reach the speed of light. This means that anything moving relative to your current
      • But it also means that you when you ask for a room with the appliances on the ceiling you will get laughed at. The OP is asking for something like this. The average layperson knows much less about chemistry than they do about living in a house.
    • Good thing nobody told these kids [] that their layman's understanding of geometry and trig wasn't sufficient to come up with something the "experts" hadn't already thought up.

      If you're a physicist and can offer some genuine critique do so. Don't tear the guy apart just because he is smart enough to ask for someone more knowledgeable to evaluate his ideas.
      • Physics/chemistry and math are not the same thing. Math is not a science. And engineering requires a sound base in physics and math, along with a lot of engineering specific rules-of-thumb that let you predict the behavior of complex systems without actually building them.

        And note none of those kids game up with new solutions to anything. Everything they did we already knew how to do. It's just they came up with different, and possibly better, ways of figuring it out. Which is an amazing accomplishment, bu

    • Because every physicist has a layman's understanding of physics. Anything that you can come up with, they've already thought of it.

      Tell it to the magnets are magic people - please! I'm tired of doing it.

      . . . then he got bored and went away.

      Because the magnet nuts never get bored or go away. They can fiddle with their "free energy" devices for frickin' ever. Their capacity to absorb failure (without ever absorbing a clue about why they fail) seems boundless. I've taken to calling them Weebles.

      Thankfully thi
    • Creativity comes in many forms. Sometimes one who knows less than experts can break out of the mental boxes we so frequently build for ourselves.

      You should also pick a better example the next time you want to flame someone.
      CRT's were originally used as storage devices.
      (e.g., see [])
    • Why? Because every physicist has a layman's understanding of physics. Anything that you can come up with, they've already thought of it.

      And yet, physics seems to slowly evolve with new idea. And a number of these ideas are from outsiders such as say a patent clerk.

    • > Because every physicist has a layman's understanding of physics.

      Yes, and every physicist was at some point a layman prior to educating himself. It's never wrong to ask questions - I probably have more respect for them than the ones that think it's stupid for doing so.

    • I have a cocksure attitude towards just about any subject you can think about. This means I can read someone's legitimate musing on a subject and sometimes (quite often, actually) trot out the tired old "oh, if that could have been done don't you think someone would already have done it?" straw dog (and trash it soundly!) That does not mean I can keep my big flapper shut. Why? Because I have to make myself at least feel like I'm superior to each and every egghead or eggheaded notion I encounter. Anythi
  • by billstewart ( 78916 ) on Monday July 24, 2006 @10:20PM (#15773588) Journal
    Different molecules have different energy levels in them - you extract energy by combining or splitting them. Different reactions also require a certain amount of energy to make them happen - you can have a reaction that will produce net energy but needs a certain temperature or amount of energy to get it started, and what catalysts do is provide alternate paths for the reaction to happen with less starting energy or lower starting temperatures.

    Combining Carbon with Oxygen or Hydrogen with Oxygen produces energy - but splitting up a chain of carbon and hydrogen to get the individual atoms to do that with requires some energy, though it's a lot less than burning the C and H will provide. Catalytic Converters on cars [] take the unburned hydrocarbons in the exhaust, split them and burn them before they get out the exhaust pipes, and take partially burned carbon monoxide and finish burning it. It's a waste of energy, but it was going to be wasted anyway - the reason to do this is that hydrocarbons and CO lead to air-pollution problems including smog. (They also split various nitrogen oxides to give nitrogen and oxygen; I don't know if this is exothermic or if it's using heat generated by the other reactions.)

    You can't split the CO2 up into C and O2 without putting back the energy you got out of that reaction, so a catalytic converter won't help you. You could do things like combine it with calcium oxide to make calcium carbonate, and store that, but the usual way to make calcium oxide is by heating calcium carbonate to get rid of the CO2, so that's really no help.

    • Maybe if the catalyst was chlorophyl and you used an energy source like, say, sunlight; and provided some fractal-like structure for the carbon deposits to grow in...

      Damn! It's already patent-pending! :)

    • Perhaps you should have read the wikipedia article you linked to? You can think of a catalytic converter as a storage tank for Oxygen. Most everything it does has something to do with its ability to attract Oxygen. For example, it reduces NOx emmissions by removing the Oxygen from the Nitrogen to store the oxygen, and passes the Nitrogen out the tail pipe.

      "...and take partially burned carbon monoxide and finish burning it."
      To the best of my knowledge, a chemical reaction that "burns" must include a hydro
      • You can 'burn' (oxidise) almost anything. For example, you can burn (and even explode) aluminium dust. Potassium (and other alkali metals) will readily burn in air (actually, it can spontaneous combust from direct sunlight).

        When you burn CO (carbon monoxide) you actually 'burn' carbon in it - CO becomes CO2.
      • by LWATCDR ( 28044 )
        "To the best of my knowledge, a chemical reaction that "burns" must include a hydrocarbon."
        Not at all. Hydrogen is not a hydrocarbon. Ever see a shuttle launch?
        "Burning" is an exothermic reaction. You don't even have to have oxygen. You can burn Hydrogen with fluorine and get a pretty good flame and a lot of heat.
        Yes CO burns very well. It was a common component of coal gas that was used for lighting in the 1800s. You can also burn a diamond in a pure oxygen atmosphere. You can even burn steel. Take some fi
  • Why? (Score:2, Insightful)

    by Anonymous Coward
    On of the big questions you have to ask yourself is, "What problem am I trying to solve?"

    The real problems facing fuel cells-the reasons why fuel cells aren't widely used-are the cost of producing them, and the difficulties in creating fuel. You're not trying to address either of those issues. In addition, you advocate replacing hydrogen fuel cells by fuel cells based on different chemisty. Making hydrogen fuel cells cheaply is hard. Now you're adding in a different, potentially brand new chemistry - you ca
    • by kfg ( 145172 ) *
      "What problem am I trying to solve?"

      Could you write that really, really big across that wall over there, the one with the forehead dents in it?

      Thanks, 'preciate it.

    • Re:Why? (Score:5, Informative)

      by CreateWindowEx ( 630955 ) on Monday July 24, 2006 @11:01PM (#15773690)
      Also, why bother to do it the hard way when you can just take something like ethanol made from switchgrass, where all the carbon came from the air originally, and then just burn it in a regular engine less than $100 of modification. If you include the additional carbon that is sequestered into the ground by the root systems of the switchgrass (harvesting is basically just mowing off the top), it actually ends up as a net loss of carbon to the atmosphere (or at least enough to compensate for using a 15% addition of petroleum for E85). Yes, ethanol in the US is made inefficiently from corn right now, but converting to a more efficient system is a political problem, not a technological one, and not an insurmountable one. See Khosla's video [] for more info.
      • Alternative fuel sources, competitive technology, cost, local preference, ...

        There's a long list of reasons why we may want to use fuels other than ethanol for our fuel cells.
      • I would like it if it could be, done but people often forget how much grass is required for such solutions, the required additional area is way to large for this planet. The same counts people who think wind energy is a solution they forget how much energy we use and thus how large the windpowerparks areas should be. I'm not happy about it neither wished it could be done. Perhaps someone has to invent a cheap sollarpannelroof cheaper then normal house roofs. Perhaps then if had such we all roofs our extra
      • Capturing carbon from the air is the hard part. If you can keep hold of that carbon and recycle it without diluting it by three thousand to one and re-concentrating it, you've saved yourself a huge amount of effort (and not having to discard the entropy saves a huge amount of energy).

        Switchgrass is far less efficient than PV panels, and some schemes yield photolytic hydrogen. If you can turn e.g. methanol and oxygen into CO2 and H2O at one end, and CO2 and hydrogen into methanol and H2O at the other, you'v

    • It would be nice to have alternatives to the current dual problems of expensive fuel cells and difficulties in creating, handling, and storing hydrogen, as well as hydrogen's low energy density and expense. Liquid fuels and onboard reformers slay the last set of problems.

      Why? Because two (or more) ways of skinnning a cat are better than one.
    • If from biomass, the CO2 question is moot - the CO2 you release today is going to be reincorporated into plants tommorrow (and thus into your fuel in a week). Zero net CO2, and you don't even have to collect any waste.

      Biomass energy is not a panacea.

      Think for a moment. The "zero net CO2" claim is only valid if you are burning biomass at the same rate as you are growing it. Burning fossil fuels would also be "zero net CO2" if there were some process by which we were coverting solar energy and atmospher

  • You can reduce more complex things like carbon dioxide or hydrocarbons to carbon with a reaction known as reduction if you have heat and something to react with. Something like hydrogen at a hot enough temperature and pressure will do it (from hazy memory) - but since the point is to have an energy source that doesn't produce CO or CO2 you don't want to consume more energy cleaning things up than you get out of your fuel.
    • Put a gaseous carbon in a balloon.. dip it into liquid nitrogen... the balloon will shrivel like cojones in alaska. . Not you could achieve that without using more energy than the fuel provides like you said.. If it were a liquified metalic salt you could plate it. . Isn't that kind of what those "Ionic Breeze" things do? Is carbon plated on the "collection grid?" It's just an ion engine right?

    • you don't want to consume more energy cleaning things up than you get out of your fuel.

      Ding! Ding! Ding!
            Mod parent up - the first poster to actually answer the submitter's question!
  • Energy levels (Score:2, Informative)

    by sf_jeff ( 988084 )
    Methane probably has more energy in it than gasoline. It has four high-energy hydrogen bonds while gasoline only has something like 2 per carbon, and the weight of a purely hydrogen and carbon hydrocarbon is pretty close to proportional to the number of carbons. Hydrogen gas has a LOT more energy in it than gasoline per unit mass. They used to power the Space Shuttle booster rockets with it before they switched to solid state fuels (Think plastic explosives). They might not have switched at all, except
  • Brilliant! (Score:2, Informative)

    This is what is known to the world as Carbon Sequestration [], and in fact many very important advances need to be made in this arena. So far, it seems that Germany is leading the world in this area, especially with their development of a carbon-emissions-free coal power plant (by actively capturing carbon in the process.)

    While I don't see much good in utilizing hydrogen-carrying fuels over non-carbon-emission methods including hydrogen itself, since one set of methods creates Carbon Dioxide and another se
  • Alright, so I'm a molecular biologist and I work with a bunch of chemists and biochemists on alternative fules. So, I have some expertise on this, but not enough that I couldn't be understood (think it though). So, here's my understanding. First off, fule cells don't make CO2, that's their big advantage. They convert H2 and O2 into H2O. If they did (and it's possible to design one that does, if you make the hydrogen on the spot from coal, which is one way to avoid running around in a car with a pressur
    • I think those ideas are nice in principal. Altough i wonder if bacteria can convert those reaction fast enough to get a car driving fast. altough this might be an idea to get rid of waste from certain types of engines.
      But I do wish you lots of luck with you science it would be nice if somthing like this can be don.

      However I think if we get into a H2 economy, it's most likely we will gonna see some nuclear plants who create H2 in mass (as it's a verry green way to create massive amounts H2 with no CO).
  • Plastic? (Score:2, Funny)

    by dredson ( 620914 )
    If you are going to get Carbon as a byproduct, why shoot for producing plastics?

    Let's making diamonds!

  • Electric vehicles are 3 times more efficient, 2.5 times cheaper today (although still too expensive), today Li-ion EVs have better range than Honda's FCX, refuelling won't be a big issue since Li-ion batteries can be charged pretty quickly these days (like within minutes to 80% capacity) but it doesn't really matter because 80% of our driving is within 35-ish km's anyway.

    Hydrogen fuel was proclaimned to be dead 2 weeks ago [] at the Lucerne Fuel Cell conference because it is not sustainable (since EVs are 3 ti
  • by Gothmolly ( 148874 ) on Tuesday July 25, 2006 @01:05PM (#15777017)
    I have an idea where we take the CO2 from the air and convert it to sugars and other chemicals needed to sustain the reaction in reactor that I call a Photosensitive Living And Natural Thing (PLANT, for short). The PLANT device catalyzes the carbon into long chains made up of broken down water molecules, so you have chemicals made with H, O and C. Let's call those "hydrocarbons". Then, we extract them, mix them with some other PLANT-derived chemicals (say something like C2H5OH), and end up with an energy-dense liquid. This liquid can then be placed in tanks, pipelines, or directly into some (wise) consumer's vehicles.

    We will call this miracle chemical "Bio-Diesel".

    45-50 mpg in the VW TDI, and my exhaust smells like french fries, baby!
  • This is a bit outside my area of expertise (diesel emission catalysts), but if you want to dive deeper into this, start with these topics:

    Fischer-Tropsch synthesis
    Bosch reaction
    Sabatier process

    All have decent Wikipedia entries.

    Chemically, I think the proposed process would be possible (i.e., you can do it in the lab.) Economically, it's probably a non-starter for this type of application. The biggest challenge in these areas is making it small, mobile, low to zero maintence, yet still inexpensive.
  • CO2 released after combustion (clean combustion) is the result of enough heat, presure and other activation energy on the fuel.

    It is, by all practical purposes the lowest energy state you can have with those items in mixture (Carbon, Oxygen).

    This is due to the fact that Oxygen likes to bond to stuff.

    Getting the carbon apart then, will take energy. Which without additional fuel additives means a catalyst won't work. The heat of oxidization of the carbon has been released and you can't re-pack heat energy w
  • So if you can get carbon monoxide out of the process - say by incomplete conversion of methanol - you can copolymerize this using late metal catalysts with something like ethylene to make alternating ethylene-CO copolymers. Not really anything useful though....
  • I've always wished there was a way to recharge a battery simply by emptying the acid out and refilling it with fresh acid, then recycling the spent acid. But unfortunately, that's not the way batteries work, it's the metal plates that are chemically altered in the process of making electricity, not the acid.

    If only someone were to devise a fuel cell that has a fresh liquid input and used liquid output, or even a Part A and a Part B mixing in the cell, and spent Part A+B coming out that could be reversed bac
  • I work for a large global company as an R&D engineer and have a material science background. The problem with Solid Oxide Fuel Cells and PEM fuel cells is that they are so efficient that there are no solid wastes. There is little to no CO2 output in the case of the SOFC either due to highly efficient reations in a properly made cell. The by products are H20 and pure heat, at about 800C to 1000C. Fuel cells have not taken off yet only because of the cost to manufacture. We are addressing this now.

"We don't care. We don't have to. We're the Phone Company."