Biological methane

U.S. capacity for producing biofuels manufactured by biological or thermal conversion of biomass must be dramatically increased to approach the potential contributions based on biomass availabiUty. For example, an incremental EJ per year of methane requires about 210 times the biological methane production capacity that now exists, and an incremental EJ per year of fuel ethanol requires about 14 times existing ethanol fermentation plant capacity. 

Ermler U, W Grabarse, S Shima, M Goubeaud, RK Thauer (1997) Crystal structure of methyl-coenzyme M reductase the key enzyme of biological methane formation. Science 278 1457-1462. 

Belay N, Daniels L. 1990. Elemental metals as electron sources for biological methane formation from CO2. Antonie Leeuwenhoek 57 1-7. 

Lieberman, R. L. Rosenzweig, A. C. Biological methane oxidation regulation, biochemistry, and active site structure of particulate methane monooxygenase. Crit. Rev. Biochem. Mol. Biol. 2004, 39(3), 147-164. 

Huang, J. J. H., and Shih, J. C. H. 1981. The potential of biological methane generation from Chicken Manure. Biotech. Bioeng., 23, 2307-2314. 

In 1946, the problem was demonstrating that the most fundamental assumptions did in fact hold. Initially, this meant obtaining measurements of the natural radiocarbon concentrations in living organics to see if it occurred in the amount expected and if the worldwide distribution of radiocarbon was essentially constant. An experiment was devised whereby biological methane gas derived from the sewage disposal plant at Baltimore, MD and petroleum methane from the Sun Oil Co. refinery were each enriched by a similar factor in a thermal diffusion column. It was assumed that the petroleum methane contained no because of its age in excess of many tens of millions of years whereas the biological methane contained about 17-18 dpm radiocarbon per g of carbon. The experiment was conducted, and the results confirmed the calculations (26). 

There is also evidence for the presence of methanotrophs in the 2.8 Ga old Mount Roe palaeosol. This contains highly fractionated organic carbon, probably recording the activity of methanotrophs living near ephemeral ponds this implies that significant biological methane sources existed in the late Archean (Rye and Holland, 2000). Oil is also present in some Archean sandstone (Dutkeiwicz et al, 1998, Rasmussen and Buick, 2000). 

Samples of biological methane ( biomethane ) obtained from a sewage disposal plant in Baltimore, Md., and of petroleum methane ( pe-tromethane ) from an oil refinery were enriched by equal amounts of in a thermal diffusion column. Whereas the activity of the biomethane increased in direct proportion to the amount of enrichment, there was no significant increase in the counting rate of the petro-methane with enrichment (4). The confirmation of Libby s prediction initiated an extensive study of the distribution of in nature. However,... 

Methanotrophs, which are widespread in aquatic and terrestrial environments, carry out methane oxidation in most habitats where methane and oxygen coexist (3). On a global scale, these bacteria are responsible for a major portion of the biological methane consumption that occurs on the earth s surface. Therefore, a great deal of interest exists concerning their role in global methane cycling (4). 

An Important area of study In organic geochemistry concerns Che origin of natural gas two of the more useful parameters In addressing this problem are 6D-CH and S C-CH. As discussed above, 6D-CH Is useful In estimating relative pathway contribution In biological methane formation. Combined with... 

Global strength of biological methane sources according to Ehhalt (1974)... 

Chloroform (trichloromethane) is a chlorinated hydrocarbon solvent used as a raw material in the production of freon and as an extractant and solvent in the chemical and pharmaceutical industry. Because of its hepatic toxicity, it is no longer used as a general anesthetic or anthelmintic agent. Chronic low-level exposure may occur in some municipal water supplies owing to chlorination of biologic methanes (tri-halomethanes). 

P. C. Wilkins, H. Dalton, I. D. Podmore, N. Deighton, and M. C. R. Symons, biological methane activation involves the intermediacy of carbon-centered radicals. Eur. J. Biochem., 210 67 (1992). 

The massive reservoir of available oxygen as ferric iron in hard rocks played a major role in the build-up to an oxygen atmosphere. Hydrogen escape to space before 2.45 m.y. produced this reservoir. Biological methane carried hydrogen to the top of the atmosphere and biological hydrogen escaped. This process has not detectably affected the oxidation state of the massive mantle reservoir. 

The biological methane potential (BMP) is probably the best test to measure the gas generation potential from a degradable carbon-based material. The BMP test... 

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