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 1786.    KLEMPT, W., AND BRODKORB, F.  [Methane-Steam Equilibrium and Its Control.]  Ber. Gesell. Kohlentech., vol. 3, 1930, pp. 220-229; British Chem. Abs., 1931, B, p. 325.

        Theoretically, at high temperatures the reaction between CH₄ and steam takes place according to the equation (1) CH₄+H₂O=CO+3H₂-48.9 kcal., while at lower temperatures it takes the form (2) CH₄+2H₂O=CO₂+4H₂-38.5 kcal.  The equilibrium constants for these two reactions have been determined only for a few temperatures, but it is possible to calculate their values from those obtained in the reactions CH₄=C+2H₂; C+CO₂=2CO; and CO+H₂O=CO₂+H₂, which are known over the range 450°-1,200°.  The constants K’_p=_pCH₄·pH₂O/pCO·pH₂ and K”_p=pCH₄·pH₂O²/pCO₂·pH₂⁴ are tabulated over the same range, but it is emphasized that the values of K’_p is limited to lower temperatures.  Calculation of the equilibrium condition shows that at 500° the cracked gas contains CH₄, 33.3%; H₂O, 33.3%; CO, 8.33%; and H₂, 25.0%; while at 940° the composition is CH₄, 0.505%; H₂O, 0.505%; CO, 24.8%; and H₂, 74.1%; when reaction (1) takes place.  A similar table is given in connection with equation (2).  Since in practice an excess of steam would be used, calculations have been made to find the effect of 2-fold and 6-fold excess of steam on the equilibrium when pure CH₄ is used.  The influence is considered of the other constituents on the equilibrium amount of CH₄ present in a gas of the following composition:  10% (CO+CO₂), 30% (CH₄+C_nH_m) 50% H₂, 10% N₂.  Temperature-composition graphs are given for both reactions (1) and (2) with this mixture.  At about 820° the CH₄ decomposes to give at equilibrium a gas containing equal proportions of CO and CO₂.