The paper examines the physicochemical features of the reduction of iron oxides (as multicomponent scale waste) in various gases: H 2, CH 4 , CO, and generator gas containing 33% CO and 67% N 2 . At the initial stage of reduction, the activity of the gases decreases in the above sequence. It is analyzed how blocking of iron oxide surface with carbon formed in the conversion of methane and carbon monoxide influences the reduction processes. The deposition of carbon in these media is intensified when the reduction degree is higher than 70%. The thermodynamic dependencies of oxide reduction on the ratio of P CO 2 /Pco partial pressures are given. Noteworthy is high sensitivity of Fe 3 O 4 and FeO reduction to the change in CO 2 content.The papers [1, 2] consider the reduction of iron oxides contained in a multicomponent mixture of metallurgical waste with the purpose of their use in hydrogen production with the iron vapor method. Metallurgy can use gases with different reducing properties, such as H 2 , CH 4 , CO, and generator gas containing different gas components. The gases differ in physical and chemical properties, which greatly determine the reduction mechanism and rate and the properties of metals reduced.This paper analyzes the effect of the above gases on the reducing processes, kinetic indicators, chemical transformations, and features of reduction products, and their effect on the surface activity of reduced oxides used in redox cycles in hydrogen production with the iron vapor method.Characteristics of the material in question containing to 70% iron oxides are provided in [1]. There are no accompanying chemical transformations during reduction in hydrogen, and no byproducts form. The use of carbon monoxide determines the probability of Boudoir's reversible reaction. Possible deposition of carbon on the surface of oxide being reduced can change parameters of chemical transformations, including the reducing mechanism. The use of methane and, possibly, mixed (H 2 , CH 4 , CO, CO 2 ) effluent metallurgical gases makes the process complex, which involves the conversion of gases in the reaction area on the surface of reduced oxides. The conversion of methane [2] can lead to the formation of hydrogen and deposition of carbon, which can change chemical processes. Active carbon may not only participate in reducing processes but also block the reaction surface of reduced oxide.Kinetic studies were conducted using an automatic gravimetric unit measuring the weight with an accuracy of 1 ⋅ 10 -5 g. This accuracy permitted analyses in different molecular and dissociated gas media at pressures between

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The paper examines the physicochemical processes that occur in the treatment of iron-containing metallurgical waste with the purpose of producing hydrogen with iron vapor method and subsequent processing the iron agglomerates. Iron oxides and reduced metal show high activity in the initial oxidation and reduction cycles. It is shown that the optimal oxidation-reduction temperature should be no more than 1000°C to prevent the intensive sintering of iron particles and decrease the activity in the reactive volume. The reduction process is most intensive in gaseous reducing medium.