733.    ---------------.  [DOMINIK, W.]  [Catalysts for the Reaction CO + H₂O = CO₂ + H₂.]  Przemysl Chem., vol. 12, 1928, pp. 229-235; Chem. Abs., vol. 22, 1928, p. 4334.

     From theoretical considerations the following equation for CO + H₂O = CO₂ + H₂ is derived:

                                               x – x       x₀ – x₂

                                                         -------- = --------- · e^-b(K-1)(x₁^-y₂^)1/V. 

                                                        x – x₁      x₀ – x₁ 

 This is like that for bimolecular reactions in homogenous systems.  b is a constant that characterizes the useful surface of the catalyst at a given temperature.  K = [CO₂] [H₂] : [CO] [H₂O] = equilibrium constant at a given temperature, V = space velocity of the gas vapor mixture in cc. per hr. per gm. of catalyst, x = partial pressure of CO₂ in the reaction mixture, x_o = partial pressure of CO₂ before the reaction, x₁ and x₂ the 2 roots of the equation

x(P₀H₂ + x-x_o)

      - K=0, in which

                                                      {P₀CO-(x-x_o)}{P₀H₂O-(x-x_o)}

P₀H₂, P₀CO and P₀H₂O represent the partial pressures of the respective components before the reaction, and only x₂, the root with the negative radical, represents the pressure of CO₂ at equilibrium.  To test this experimentally the extent of the reaction was measured after the gaseous mixture had passed over 1 and over 2 equal portions of the catalyst under the same conditions.  A whole series of determinations shows that the catalysis of water gas does proceed according to the derived equation, but that possibility of small differences of temperature lowers the accuracy of the determinations.