3405.     TIMASHER, A. S.  [Reduction of Complex Chemical Compounds in Relation to Their Dissociation.]  Metallurg., vol. 14, 1939, No. 3, pp. 19-28; Jour. Iron Steel Inst. (London), vol. 140, 1939, A, p. 257.

        Reduction of ferric, ferroso-ferric, and ferrous oxides with CO at 500 was studied in an apparatus in which a stream of CO was passed over the heated oxides, provision being made for continuous and automatic recording of the temperature and the CO2 content of the exit gases.  Preliminary tests had shown that at temperatures used, Fe had a negligible catalytic effect on the reaction 2 CO=CO2+C.  The reduction of the ferric oxide took place in 2 stages, the 1st being irreversible and leading to the formation of 100% CO2 (3 Fe2O3+CO=2 Fe3O4+CO2).  The 2d stage corresponds to the reduction of the ferroso-ferric oxide with formation of a gas mixture of 47% CO2 and 53% CO.  the ferroso-ferric oxide is reduced directly to metallic Fe (Fe3O4+4 CO=3 Fe+4 CO2).  Under the experimental conditions the reduction of the ferrous oxide took place in 2 ways, namely, FeO+CO=Fe+CO2 and by a complex reaction, the net result of which is represented by the reaction 4 FeO=Fe3O4+Fe.  The whole of the ferrous oxide is decomposed at the beginning of the reduction, which afterwards consists of the reduction of the ferrosoferric oxide.