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Carbohydrate-Based Synthesis To Replace Petroleum Derived Hydrocarbons?

someWebGeek writes "From PhysOrg's 'Taking biofuel from forest to highway,' University of British Columbia biofuel expert Jack Saddler says, 'we will become less dependent on fossil fuels and will become more dependent on fuels made from the sugars and chemicals found in plants.' Nothing too new there; the idea of biofuels eventually taking over from petroleum distillates has been around for ages. However, Saddler contends further that 'Similar to an oil refinery that processes crude oil to make thousands of supplementary products like plastics, dyes, paints, etc., the biorefinery would use leftover agricultural and forest material to make many of the same products, but from a sustainable and renewable resource.' I remember my organic chem instructor back in '81 telling us that eventually the textbooks would have to be rewritten. There would be no presumption of fractional distillation of thousands of basic compounds from petroleum, and the teaching emphasis would shift to synthesis from simple hydrocarbons. He noted that we'd all miss 'the good, ole days' when synthetic fibers, plastics, etc. were cheap... or even an economically viable option. I can live without rayon, but, dang, I'm gonna miss polyvinyl chloride!"

8 of 166 comments (clear)

  1. End of oil for fuel != end of oil. by Bonobo_Unknown · · Score: 3, Informative

    Oil isn't going away any time soon. The fact is that for a very long time after it no longer makes sense to burn oil for fuel that oil will be available and will still make economic sense to use as a precursor product for all of those complex compounds that currently can only be made from oil. Perhaps in the far, far future it will become necessary to reinvent processes to build these things out of other precursors, but not for a long time. There's still going to be plenty of that black gunk in the ground long after people stop being able to burn it to get from A to B.

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  2. Re:Death Throes by 0123456 · · Score: 3, Informative

    One has to wonder just how hard the petroleum industry will fight these developments, though.

    Until we have a better means of producing the carbohydrates, I'm guessing you'll see more death throes from the people who are starving because of the food we'r'e not growing.

  3. Re:Factor in one more thing though? by Anonymous Coward · · Score: 0, Informative

    If crude oil costs $100/bbl and you had to burn 10 of them to make 1bbl of veg oil, veg oil would have to cost $1000/bbl, or $23/gal. Right now you can get veg oil for $5/gal as some place like Costco.

    dom

  4. Rayon isn't synthetic by Seraphim1982 · · Score: 4, Informative

    Out of all the examples you could pick you picked rayon? Rayon is produced using cellulose (wood), sodium hydroxide, carbon disulfide and sulfuric acid. It isn't a synthetic fiber, and there isn't any petroleum involved in the process. Rayon is just cellulose that has been dissolved and regenerated as a fiber.

  5. Re:Factor in one more thing though? by TheInternetGuy · · Score: 5, Informative

    If you have to burn 10 barrels equivalent of crude oil to make 1 barrel equivalent of food grade veg oil

    I have read and heard this so many time here on Slashdot now, and I am gonna call you on it.
    If it takes a ratio of 10:1, crude to produce vegetable oil. Then how come a cheap vegetable oil can be found for a 3-4 bucks a gallon?
    While the cost of 10 gallon of crude costs 30-40 dollars?
    Are the producers just giving us all that crude for free out of the goodness of their hearts?
    Seriously people use your brains, think for your selves.

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  6. Re:Another couple of factors by TheInternetGuy · · Score: 5, Informative

    Right now, I've read we're burning about 400 years worth of laid-down plant carbohydrate per year, in the form of fossil fuels. That's right. To obtain the equivalent amount of energy from non-fossil biofuels as we're currently getting from fossil fuels, we'd have to increase the amount of plant material being grown on Earth by a factor of 400 times

    No that is not what it means at all, in any way shape or form.
    What it means is that we are using fossil fuel at an rate of 400 times of which new fossil fuel is produced by natural processes. Only a small percentage of biomass will ever become trapped in the correct anaerobic environment and then fossilized over millions of years. So there is lots of biomass available for use as fuel.

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  7. Re:Another couple of factors by compro01 · · Score: 3, Informative

    Your figure assumes that 100% of the plant matter per year is transformed into coal/oil/etc. This is not even close. Only about 0.0093% of the carbon in plant matter becomes fossil fuels. The remainder stays in the carbon cycle.

    That comes to 3.72% of annual plant matter generation to supply the same energy. Though probably at least double that to account for efficiency.

    Whether that amount is sustainable is left as an exercise for someone else.

    http://plus.maths.org/content/burning-buried-sunshine

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  8. Re:Wood wasn't enough to fuel the Middle Ages by bertok · · Score: 5, Informative

    Trees are about as effective in doing photosynthesis as any other plant.

    That's not true, there's significant differences in efficiency between various species of plants. Most grasses for example are much more efficient than trees, which is why grassland can support huge herds of large animals, but a forest can't.

    See: Photosynthetic Efficiency, where it has a table of some typical efficiencies:

    Plants, typical : 0.1%
    Typical crop plants: 1-2%
    Sugarcane: 7-8% peak

    This is because more than one kind of photosynthesis has evolved, with somewhat different chemical processes. Look up C3 carbon fixation and C4 carbon fixation for the differences.

    There is a significant research effort going on looking into ways of taking the genes for the more efficient types of photosynthesis and merging that into less efficient plants. This could be used to make fruit trees grow much faster, or to create algae that can be used to produce alcohol or oil at efficiencies approaching those of solar electric power.