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Co2 to Coal

  1. Jan 31, 2010 #1
    I'm new here and I'm in no way a Science person or a Eco person. The fact is that I'm an Accounting major with an idea.

    Would it be possible to take CO2, remove the oxygen and concentrate the Carbon into coal?

    I got this idea while watching part of a "green" show. They were showing how this group of people where pumping CO2 into the ground. I just thought it would be neat to see if this was possible.

    Like I said, I haven't taken Chemistry since High School and while in college I took Earth Science.
  2. jcsd
  3. Jan 31, 2010 #2


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    It is possible, but you need to consider the thermodynamics. Chemistry is not like accounting where you can convert your money into stocks then convert the stocks into money and come out with a profit. Any chemical conversion involves a net loss of usable energy. Therefore, it would take more energy to convert CO2 into coal than the energy you could generate from burning that same amount of coal (or else you would essentially have a perpetual motion machine, breaking the 2nd law of thermodynamics).
  4. Jan 31, 2010 #3


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    I don't know too much about the chemical structure of coal, but I would imagine it would be much easier just to plant a bunch trees.

    Though people are working similar ideas to your own:

    though he goes on to say:

    As an accountant, you should well know that if your expenses exceed your profits, then there's no private industry in the world that is going to fund your idea.

    Hence, just spit apple seeds all over your yard. It's cheap, and does the same thing. Personally, I've got bing cherry trees all over my property. When they get too tall, I chop them down, burn them in the wood stove, and plant more seeds.

    And I should point out that https://courseware.e-education.psu.edu/courses/egee101/L03_coal/L03_coal_origins2.html" [Broken].

    And burning wood isn't all that horrific in terms of energy per pound as compared to coal:

    Especially considering the cost. If you're a seed spitter that is.
    Last edited by a moderator: May 4, 2017
  5. Jan 31, 2010 #4
    Planting trees is certainly easy. Whether it's cheaper than direct CO2 to coal conversion using solar power, that remains to be seen. Trees grow extremely slowly, it can take 20 years to grow a decent size tree from seed. You have to set aside a piece of land that could've otherwise used to generate profit, either by building a house, a road, using it to grow foodstuffs, laying solar panels or building wind turbines. Trees may need to be irrigated.

    And the worst thing about trees vs. coal, is that coal is a relatively inert substance, and trees easily decay. Dead leaves will decay within a year or two, releasing 100% of captured carbon back into the atmosphere. Tree trunks take longer, but they too will release carbon, making the entire exercise futile - unless you go to extreme pains to protect them from decay, perhaps by burying them in abandoned mines and then sealing them with concrete.
  6. Jan 31, 2010 #5


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    That's some fancy economic theory you've got going on there if you can tell me how popping a cherry seed onto the ground cost me anything.
    Yup. No more "flip that house".
    I've over 50 tree's on my 6000 ft lot. Two are in my way: Firewood for next winter!
    And you're right about foodstuffs. Two cherry trees were encroaching on my garden, so I chopped them down and turned them into tomato trellises.
    Bwah. hahahahahahaha!
    The only reason I've ever watered a tree was because I was bored.
    Indigenous tree's do not need to be watered.
    Concrete? When did tree's become the equivalent of plutonium waste?
    Let them rot?!
    What part of using them as a replaceable fuel did you not understand?

    Let's start over:

    1. spit seed
    2. tree grows and converts CO2 into coal precursor.
    3. tree gets too big and is converted to fuel, replacing non-carbon neutral oil, gas, and coal.
    4. repeat
  7. Jan 31, 2010 #6
    It did not cost you anything, because you weren't utilizing that land properly to begin with. You also didn't gain anything (not right away). If we want to talk about large-scale carbon sequestration, cost of land is a factor to be considered.

    They must be really small. A single fully grown oak tree can have the canopy 6000 sq ft. in area.

    Depends on where you live. In much of the United States you can go around spitting cherry seeds all day and nothing's going to happen. Freeway 35 is the approximate western boundary of the part of the country where trees grow naturally without irrigation. Further west, there are no "indigenous" trees, just yucca and various kinds of cactuses.

    There was nothing about using them as a replaceable fuel in the original proposal. We were talking about carbon sequestration by the means of tying atmospheric CO2 in some form.
  8. Feb 1, 2010 #7


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    Oh. Why didn't they say so. I'd have just told them to plant some trees. It's free and requires no maintenance.

    I guess I couldn't imagine turning CO2 into coal for sequestration on the one hand, and mining it in the next county to run your electric plants. It simply doesn't make sense.
  9. Feb 1, 2010 #8
    I was just asking a question and didn't appreciate the patronizing about me being an accounting major. Like I said I am not a science nerd and I was just curious. I just wanted to know if it was possible. I knew there would be some time of loss. I wasn't sure.

    I was wondering not for profit, but because I am always hearing about the tons of CO2 pumped into the atmosphere. I thought that if there was a way of concentrating it would make it better for the environment.

    I might be an accounting major and not a science nerd, but I don't think like an accountant all the time. Thanks, I won't be back.
  10. Feb 2, 2010 #9


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    Sorry to hear that you feel that way, but for what it's worth, none of the answers in this thread were patronizing in the least. Only the first two replies were specifically in response to your questions, and the posters simply stated facts or opinions in an attempt to give you the answer you were seeking. From my point of view, the posters were doing their best to put concepts from chemistry (a subject you indicated you were unfamiliar with) into an economic context that might make them easier for you to understand.

    As you can see from their responses, you are in fact correct about your idea, and people are working on exactly the sort of ideas you proposed, but none of them are close to being economically viable. The posts were to the point and informative ... I guess I don't understand why you felt they were patronizing you.
  11. Feb 2, 2010 #10


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    Here is a http://www.tms.org/pubs/journals/jom/0802/neelameggham-0802.html" [Broken] arranged around just your idea.
    Last edited by a moderator: May 4, 2017
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