Production of hydrogen carbon

Direct oxidation of methane (natural gas) with tonnage oxygen of about 95 per cent purity is assuming increasing importance in connection with the production of hydrogen-carbon monoxide synthesis gas, raw material for the American modified Fischer-Tropsch synthesis of liquid fuels and chemicals. ... 

S. Michel Low Cost Production of Hydrogen, Carbon Monoxide and Synthesis Gas. 

As an example of the application of a fixed-bed tubular reactor, consider the production of methanol. Synthesis gas (a mixture of hydrogen, carbon monoxide, and carbon dioxide) is reacted over a copper-based cat dyst. The main reactions are... 

Table 10.14 provides some essential information concerning the production of hydrogen by partial oxidation of a VR. By-products are carbon dioxide and hydrogen sulfide. 

Commercial-scale processes have been developed for the production of hydrogen sulfide from heavy fuel oils and sulfur as well as from methane, water vapor, and sulfur. The latter process can be carried out in two steps reaction of methane with sulfur to form carbon disulfide and hydrogen sulfide followed by hydrolysis of carbon disulfide (116). 

This is the reverse of the water-gas shift reaction in the production of hydrogen and ammonia (qv). Carbon dioxide may also be reduced catalyticaHy with various hydrocarbons and with carbon itself at elevated temperatures. The latter reaction occurs in almost all cases of combustion of carbonaceous fuels and is generally employed as a method of producing carbon monoxide. 

To reduce soil acidity and keep cropland productive, farmers amend the soil by liming, which is the application of limestone. Limestone is calcium carbonate, and the carbonate anion is the conjugate base of hydrogen carbonate. Liming therefore increases the concentration of hydroxide in the soil, thereby increasing the pH C03 ((3 q) + H2 0(/) HC03 (<3 g) + OH (<3 q)... 

Figure 2 shows the result of an experiment without photocatalyst where the reactor tenperature was maintained at 97°C during the run. Note that conversions of methane remain relatively constant at - 4% and production of hydrogen, methanol, oxygen, and carbon monoxide remain constant during the ejqjeriment. The large oscillations in the conversion of methane and the production of methanol were not observed during this ejqjeriment. 

Figure 18. Ion beam sputter deposition apparatus for the production of hydrogenated amorphous carbon. (Reproduced with permission from Ref. 26, Copyright 1985, AIP).

Pyrolysis of methane under the action of pulsed microwave radiation in the presence of solid catalysts has been reported by Russian authors [71, 72], The application of pulse microwave power was shown to be a promising means of production of hydrogen syngas, ethyne, and filament carbon. 

Ermakova, M. and Ermakov, D., Ni/SiOz and Fe/Si02 catalysts for production of hydrogen and filamentous carbon via methane decomposition, Catal. Today, 77, 225, 2002. 

Steinfeld, A. et al., Production of filamentous carbon and hydrogen by solar thermal catalytic cracking of methane, Chem. Eng. Sci., 52,3599, 1997. 

In conventional production of hydrogen from coal, as described earlier, coal is converted to hydrogen and carbon monoxide (CO) through the water-carbon reaction as shown in reactions 3.9 through 3.11. CO is then converted to hydrogen and carbon dioxide by the water-gas shift reaction as shown in reaction 3.12. 

Han, C. and D.P Harrison, Simultaneous shift reaction and carbon dioxide separation for the direct production of hydrogen, Chem. Eng. Sci., 49, 5975-5883,1994. 

Substitution products of the carbon-bonded hydrogen were obtained. A synthesis of coenzyme Q, was achieved in this way (example 6, Table IV). The site of attack in quinones is highly specific and corresponds to the noncarbonyl ring site of highest spin density of the quinone radical anion (lOg, 127). 

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