1787. ---------------. [KLEMPT, W., AND BRODKORB, F.] [Water-Gas Equilibrium and Its Control.] Ber. Gesell. Kohlentech., vol. 3, 1930, pp. 261-274; British Chem. Abs., 1931, B, p. 325.

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Literature Abstracts

Theoretically, the known values for the equilibrium constant of the reaction CO+H₂O=CO₂+H₂ over the range 327°-2,090° indicate that at higher temperatures the equilibrium is in favor of CO-steam. To favor the production of H₂, as low a temperature as is compatible with suitable reaction velocity must be chosen. The use of catalysts alone does not materially assist in the complete removal of CO from the gas at temperatures at which it is practicable to work. The theory is discussed of the disturbance of the equilibrium by use of excess of steam and by removal of the CO₂ formed simultaneously with the H₂ by absorbents such as lime. The pressure of CO₂ in the system CaCO₃-CaO-CO₂ limits the temperature at which the latter method of disturbing the water-gas equilibrium can be used to an extreme of 600°. In practice, lower temperatures would have to be used. This theoretical study leaves no doubt that the removal of CO₂ is the more practicable method of achieving a good conversion of the CO. Thus, at 550°, to reduce the steam- and CO₂-free gas to the same CO content as that produced by the passage over lime, using 1 vol. of steam, requires a volume of steam 20 times that of the CO. By using a slight excess of steam in conjunction with CO₂ removed at this temperature, the CO can be reduced to a mere trace. The foregoing considerations are applied to the gas resulting (abs. 1724) from the action of steam and air on CH₄.