3373.     TERRES, E., AND PONGRACZ, A.  [Reactions in the Blast-Furnace Equilibrium.]  Ztschr. Elektrochem., vol. 25, 1919, pp. 386-407; Chem. Abs., vol. 14, 1920, p. 919.

        Reversible reaction represented by the equation Fe+CO₂=FeO+CO has been studied and the equilibrium ratio of the gases determined at temperatures 550°-950° by approaching the equilibrium from both sides and varying the quantities of the starting materials.  On plotting the ratio of the initial gas concentration, CO₂ or CO, to the equilibrium concentration of the mixed gases, CO₂+CO, at equilibrium against the equilibrium temperature, a curve is obtained, which, in agreement with the results of Schenck and his coworkers and in disagreement with those of Baur and Glaessner, shows no minimum and is almost linear.  It has been found that the quantity of Fe exerts an influence on the system, the position of equilibrium being displaced so as to favor the formation of CO as the amount of metal is increased.  An analytical method and special apparatus have been developed for determining quantitatively in a mixture the amounts of Fe in the different states of oxidation.  The action of CO₂ on Fe in a closed vessel results in the formation of both FeO and Fe₂O₃, from which the existence of solid solution is deduced by means of the phase rule.  In conclusion, it is shown that at higher temperatures Fe can probably absorb considerable quantities of CO₂ and CO.