Methane and Ammonia Oxidation

The production of reduced products like methane and ammonia by the gut microbial flora has important environmental consequences, as such compounds contribute to the chemical and biological oxygen demand. The detection of dissolved oxygen in the gut of piglets led to tests to show whether methane and other reduced products could be oxidized in the pig gut. The production of C-labelledCOj from C-labelledmethane has been demonstrated however, it is calculated that at most only a very small proportion of methane produced is likely to be oxidized using O 2 as electron acceptor. Methane may also be oxidized anaerobically, but only an extremely small amount of methane is likely to 

Tests on pig gut contents using molecular probes to detect the presence of (aerobic) ammonia oxidizers proved negative. Recently, the anaerobic oxidation of ammonia coupled to nitrate reduction has been demonstrated in 

Archer and J. E. Harris, in Anaerobic Bacteria in Habitats Other than Man, ed. E. M. Barnes and G. C. Mead, Blackwell Scientific Publications, Oxford, 1986, pp. 185-223. 

Hillman, A. Whyte and C.S. Stewart, Lett. Appl. Microbiol., 1993, 16, 299. 

Hillman, H. van Wyk, E. Milne, C.S. Stewart, and M.F. Fuller, in Symposium on Global Methane Flux, Abstracts, Society for General Microbiology, 1995, p. 24. 

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Erwin DP, IK Erickson, ME Delwiche, FS Colwell, JL Strap, RL Crawford (2005) Diversity of oxygenase genes from methane- and ammonia-oxidizing bacteria in the Eastern Snake River plain aquifer. Appl... 

Steam Reforming Processes. In the steam reforming process, light hydrocarbon feedstocks (qv), such as natural gas, Hquefied petroleum gas, and naphtha, or in some cases heavier distillate oils are purified of sulfur compounds (see Sulfurremoval and recovery). These then react with steam in the presence of a nickel-containing catalyst to produce a mixture of hydrogen, methane, and carbon oxides. Essentially total decomposition of compounds containing more than one carbon atom per molecule is obtained (see Ammonia Hydrogen Petroleum). 

Ammonia production from natural gas includes the following processes desulfurization of the feedstock primary and secondary reforming carbon monoxide shift conversion and removal of carbon dioxide, which can be used for urea manufacture methanation and ammonia synthesis. Catalysts used in the process may include cobalt, molybdenum, nickel, iron oxide/chromium oxide, copper oxide/zinc oxide, and iron. 

Gauzes are the state of the art for many millisecond-reactions performed in industry. The best-known examples are the oxidation of ammonia to NO for the production of nitric acid and the Andrussov process, in which HCN is produced from methane and ammonia (32) ... 

Other substrates reduced by nitrogenase include azide (which gives ammonia, dinitrogen, and hydrazine) (151), diazomethane (ammonia and undisclosed products), nitrous oxide (dinitrogen and water), hydrocyanic acid (methane and ammonia), cyanide (methane and ammonia), methyl isocyanide, and other organoisonitriles (methylamine, methane, ammonia, ethane, and other higher hydrocarbons). 

Andrussov oxidation. Ammonia and methane are oxidized with air in the presence of platinum catalyst to form hydrogen cyanide. Side reactions are hydration of methane to carbon dioxide and hydrogen, and oxidation of methane and ammonia to carbon monoxide and nitrogen. The reaction is strongly exothermic. The process has been elaborated wherever natural gas is abundant. 

Hydrogen Is the most common element In the solar system (It constitutes about 87% of the sun s mass). It therefore seemed reasonable to think that, when the planets were formed, other elements should have been present In reduced (not oxidized) forms carbon as methane, nitrogen as ammonia, and oxygen as water. Indeed, some of the outer planets (Saturn and Jupiter) still have atmospheres that are rich in methane and ammonia. 

The most important process is the Andrussov oxidation invented by Leonid Andrussow at IG Farben in which methane and ammonia react in the presence of oxygen at about 1200 °C over a platinum catalyst ... 

The energy needed for the reaction is provided by the partial oxidation of methane and ammonia. 

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