3187.     ŠIMEK, B. G., AND KASSLER, R.  [Conversion of Carbon Monoxide by Water Vapor on Iron Catalysts.]  Chim. et ind. Special No., April 1934, pp. 330-337; Chem. Abs., vol. 28, 1934, p. 5626.

        In order to ascertain the part played by secondary reactions in the catalytic conversion of mixtures of water gas and water vapor over Fe catalysts, comparative tests were carried out with reduced aluminoferric and with pig Fe, both activated with K₂CO₃, with the following results:  (1) at 500°, the reduction of the catalyst to oxide by CO alone stops before liberation of metallic Fe.  (2) The metallic Fe formed by reduction at 500° with H₂ alone is oxidized by H₂O, so that the catalyst is in equilibrium with the gaseous phase.  (3) the C liberated by known decomposition of CO on Fe catalysts, starting at 500°, can be gasified by H₂O, so that the homogeneous conversion of water gas over an Fe catalyst can be considered as the resultant of several reactions taking place successively in heterogeneous medium.  (4) The importance of the conversion reaction proper, as compared to the decomposition of CO, was determined under varying conditions of flow, with reduced Fe and pig Fe as catalysts.  (5) The catalyst prepared from pig Fe has a lower efficiency than the precipitated catalyst, but the secondary reactions are more intense in the former case than in the latter; their importance, however, decreases when the rate of flow is increased above a certain value.  (6) H₂S exerts a poisoning action on the reduced precipitated Fe catalyst.  (7) The degree of conversion over precipitated catalyst varies with the flow and exhibits a maximum for a definite flow, which itself depends on the temperature; the degree of conversion over activated pig Fe also exhibits a maximum, which does not correspond to a minimum of the secondary reactions.