Slashdot Mirror
Making Fuel With Newspapers and Bacteria
Debuting on the front page, Lifyre writes "Scientists at Tulane have found a natural bacteria (dubbed TU-103) that produces butanol. While butanol-producing bacteria aren't new, there are a few important points about this particular bacterium. It is the first natural bacteria that converts cellulose directly to butanol without the cellulose needing to be processed into sugar first, and it can do this in the presence of oxygen, which kills other butanol-producing bacteria. The simplification of the process could significantly decrease the production costs of butanol. This bacteria could allow virtually any plant product, such as newspaper or grass clippings, to be used to produce fuel for conventional vehicles."
First off, if it is n-butanol that is being produced, the water solubility of n-butanol (at 25 C) would only allow a ~6% concentration, thus the rest would float to the surface and would be easily skimmed off in a moderately pure state. Now I don't know the temperature dependence of the solubility so perhaps this wouldn't be practical at fermentation temperatures.
Similar research is being done by Dr. Shota Atsumi et. al; they produced an organism with an engineered metabolic pathway which can produce isobutyraldehyde. This compound has a lower boiling point such that at the elevated temperatures of fermentation it is easily distilled from the culture without having to kill or filter the bacteria. Again, the issue of culture toxicity due to the metabolic product is avoided through in situ purification of the product.
Yes, cellulose is a polymer of simple sugars. However most organisms lack the enzymes to break the chain up into its individual units. Ruminants and termites have symbiotic bacteria that digest it for them, and some species of fungus can break down cellulose (think mushrooms on a fallen tree) but as it stands, using cellulosic feedstocks require breaking up the chain via enzymes (expensive) or acids (nasty) so that bacteria can utilize it. And yes, newspaper does burn quite well, but I'd like to see you stuff it in your gas tank.
Given that nature is, in rough approximation, a large mass of meat eating itself(with enough solar meat to save the system from heat death), I'm inclined to doubt it.
It would certainly try; but the world is already quite full indeed of vicious little organisms who want nothing more than to break the world down into its simple sugars, and the equally cunning countermeasures deployed against them by their intended victims. It is unlikely(though not 100%) impossible, that somebody's pampered little high-yield laboratory specialist would make much of a mark on the mean, mean, microbial streets...
A larger component percentage of the fiber in newsprint is hemi-cellulose and lignin than cellulose. Newsprint is generally made in a mechanical process rather than a chemical process so you are going to be left with all the turpentine and tall oil in the pulp as well. Are you going to just burn the rest? It seems awfully wasteful given how expensive your process is going to be. It is generally accepted that when it comes to newsprint, it is better to burn it than to recycle it as the fuel expended in the collection of it and energy and chemicals expended to de-ink it outweigh the value of the crappy chewed up fiber you get from recovering it. I am a process engineer in a paper mill