Carbon to methane

Hydrogenation of the oxides of carbon to methane according to the above reactions is sometimes referred to as the Sabatier reactions. Because of the high exothermicity of the methanization reactions, adequate and precise cooling is necessary in order to avoid catalyst deactivation, sintering, and carbon deposition by thermal cracking. 

At elevated temperatures, the hydride reduces carbon dioxide or sodium hydrogen-carbonate to methane and ethane. The latter are probably the explosive reaction products produced when carbon dioxide extinguishers are used on LAH fires. 

All the elementary steps in the hydrogenation of carbon to methane, nitrogen to ammonia, and oxygen to water on Pt(lll) were investigated, i.e., reaction pathways for the following reactions were determined ... 

Experiments with C- and H-acetate showed that the methyl group of acetate is the major precursor of methane and the carboxyl-carbon is oxidized to CO2, providing electrons for reduction of the methyl-carbon to CH4 [7,231,232]. However, Krzyeki et al. [233] showed that 14% of the methane produced by whole cells of an acetate-adapted strain of M. barkeri originated from the carboxyl-carbon, and an equivalent amount of CO2 came from methyl-group oxidation the reduction of carboxyl-carbon to methane has also been observed in extracts [7,234]. 

Figure 4 Diagram ps versus pH for the system Fe-C02-H20. The solid phases are Fe(OH)3 (amorphous), FeCOs (siderite), Fe(OH)2(s), and Fe(s) Ct = 10 M. Lines are calculated for Fe(II) and Fe(III) = 10 M at 25 °C. The possible conversion of carbonate to methane at low ps values was ignored (source Stumm and Morgan, 1996).

Donors and Donees in Permanent Contact.—A spillover mechanism has been put forward to account for the catalysis of the hydrogenation of high area carbon to methane by impregnated metals.The activity series found (Rh >... 

The above-mentioned evidence relating carbidic surface carbon to methanation and to FT synthesis raises the question how the reactivities of COajs and compare. This additional information, discussed in the following two sections, is indispensable for deciding whether or not C-O bond breaking is a slow step in the synthesis, and whether or not hydrogenation of carbidic carbon is kinetically significant in the presence of CO, that is, in the FT synthesis proper. 

Scaleup of the FDP Reactor. The FDP reactor has two important functions it must convert the coal to a nonagglomerating char for the subsequent fluid bed and it must convert enough carbon to methane so that the FDP product gas is, after acid gas removal and light methana-tion, an acceptable pipeline gas. 

Figure 15. Fractional conversion of carbon to methane for KHCOs-catalyzed char A at 500 psi, 950°C...

Processes described in this chapter include (1) thermal oxidation of VOCs and odors, (2) catalytic oxidation of VOCs and odors, (3) catalytic oxidation of sulfur compounds to sulfur oxides, (4) catalytic conversion of organic sulfur compounds to hydrogen sulfide, (S) conversion of carbon monoxide to carbon dioxide (shift conversion), (6) conversion of oxides of carbon to methane (methanation), and (7) conversion of acetylene to ethylene (selective hydrogenation). 

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