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skrap1r0n
2005-Sep-08, 06:02 PM
here's an article (http://www.discover.com/issues/may-03/features/featoil) I just found from May of this year in Discover Magazine. (login from bugmenot is crash@jacklondon.net / e4553f7b)

I find this fascinating. My question would be this then. IN tha last few paragraphs of the article they begin to talk about the processes effect on global warming. Throughout the article they state that they can process anything with carbon in it. Now, that being said, would it be possible to process the CO2 in our atmospehere into useable byproducts?

Nowhere Man
2005-Sep-08, 06:55 PM
I don't think so. TDP generally breaks down complex molecules, like proteins and polymers, into simpler hydrocarbons which can then be used for fuel. To do this with CO2 would be to run the basic reaction

CH4 + 2*O2 --> CO2 + 2*H2O + energy

backwards. You'd have to put energy into it, and since thermodynamics is a one-way street, you'd still be putting in more energy then you get out.

Fred

Swift
2005-Sep-08, 08:37 PM
Nowhere Man is right about having to put energy into it. If all one wanted to do was convert CO2 into something useful, and you were willing to spend the energy, you can do it. There are two ways, "traditional" chemistry (like in a petrochemical plant) or biologically (plant a bunch of crops, harvest them, convert the plant matter into polymers). Both require putting a lot of energy into the processes.

Halcyon Dayz
2005-Sep-08, 08:43 PM
Yes, but farms are solar powered.

Swift
2005-Sep-09, 06:42 PM
Yes, but farms are solar powered.
That was my point (and I know you winked and I'm being serious now). The plants are solar powered, but the tractors and all the other equipment are not, not to mention the processes to convert the plant matter into something like a polymer.

jkmccrann
2005-Dec-19, 02:19 PM
A very interesting article there, and I particularly like the fact that they're very keen to stress that their process is neutral in regards to global warming, they're obviously trying to appeal to the greenies with that pitch because their process is surely something that wouldn't be at the forefront of greenie solutions to global warming.

HenrikOlsen
2005-Dec-19, 02:29 PM
Is there a reason for resurrecting this thread?

Swift
2005-Dec-19, 07:11 PM
A very interesting article there, and I particularly like the fact that they're very keen to stress that their process is neutral in regards to global warming, they're obviously trying to appeal to the greenies with that pitch because their process is surely something that wouldn't be at the forefront of greenie solutions to global warming.
I can not speak for all "greenies", but this greenie at least is interested in investigating all possible solutions to our dependence on oil and natural gas as both energy and raw material sources.

TheBlackCat
2005-Dec-19, 08:45 PM
Is there a reason for resurrecting this thread?
Is there ever a reason with jkmccrann?

trinitree88
2005-Dec-20, 12:59 AM
There's a use for carbon dioxide in fire extinguishers and as dry ice in cryo applications of course...it's produced as a by-product by outfits like AIRCO...who make their money by liquifying air, and selling of the nitrogen, oxygen, carbon dioxide, xenon, ..etc. Yes it takes energy to do that. One of the odd things though is magnesium fires and CO..sub 2. Magnesium will remove the oxygen from it if you try to put out a magnesium fire with a carbon dioxide extinguisher. During WW2 bombers used magnesium struts as they were strong but lighter than aluminum....but when they caught fire, a carbon dioxide extinguisher wouldn't put them out. Bomber crews learned that the hard way, unfortunately.
P.S. If you've got an old magnesium ladder around...beaten up....and a summer campfire..dark night....hacksaw.....you'll come up with a brilliant idea..if you think magnesium ribbon was fun in chem class...it will extinguish piled deep in sand though.

wayneee
2005-Dec-20, 01:32 AM
Your talk of plants reminds me of that Quote Paraphrase " When will science advance to where nature has been all along"
As we know CO2 is constantly absorbed, but not in the Rain forest as most people think , but in the oceans by little folks in the plankton world which out number Photo cells on terra by 200 to one. Want to absorb more CO2 , Aid Planktonic life, stop polluting Oceans. I know , never happen.

Swift
2005-Dec-20, 04:25 AM
Your talk of plants reminds me of that Quote Paraphrase " When will science advance to where nature has been all along"
As we know CO2 is constantly absorbed, but not in the Rain forest as most people think , but in the oceans by little folks in the plankton world which out number Photo cells on terra by 200 to one. Want to absorb more CO2 , Aid Planktonic life, stop polluting Oceans. I know , never happen.
In some ocean eco-systems, a lack of iron is the limiting factor for the amount of plankton. There have been some large scale experiments that have tested the idea of fertilizing oceans with iron, to increase plankton production and the uptake of CO2 (link (http://www.cem.msu.edu/~cem181h/projects/96/iron/cem.html)). I believe the decision was that such schemes were not practical on a global basis.

TheBlackCat
2005-Dec-20, 06:26 AM
I read about that a while. One researcher even said on the subject (half-jokingly):

Give me a half a tanker of iron and I'll give you the next ice age

wayneee
2005-Dec-20, 06:54 PM
I read about that a while. One researcher even said on the subject (half-jokingly):
Weve been sinking Iron into the ocean for a hundred years, with all the wars.

trinitree88
2005-Dec-20, 07:39 PM
It's the concentration in the upper layers of the ocean that's critical. Instead of dumping, say Ferrous Ammonium Sulfate, in the ocean at large...chelated iron was attached to time release capsules that floated, they'd bloom. You might get red tides and other undesirable effects though. Probably not an experiment to get carried away with.

wayneee
2005-Dec-21, 02:57 PM
it took me a bit of Googling to jumpstart my memory of its exact name. Diatoms are and were the key to Carbon assimulation. These I believe will be crucial to Us , and prehaps any future Terra-forminghttp://www.jgi.doe.gov/News/news_9_30_04.html

I had a proffesor that I thought was going to marry a Diatom.

publiusr
2005-Dec-21, 09:15 PM
Must have been a small cake.