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, xo = partial pressure of CO2 before the reaction, x1 and x2 the 2 roots of the equation

x(P0H2 + x-xo)

      - K=0, in which

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

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.