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 1^st 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.