CALCULATION OF THERMODYNAMIC TEMPERATURES OF CHEMICAL REACTIONS OF STEPWISE MANGANESE REDUCTION PROCESS FROM ITS DIOXIDE BY CO GAS AND GASIFICATION OF SOLID CARBON BY DEGREES OF CHEMICAL AFFINITY OF SUBSTANCES TO OXYGEN

The results of a thermodynamic analysis of the course of chemical reactions of the stepwise reduction of manganese from its dioxide by CO gas and the gasification reaction of solid carbon (Bella-Boudoir) are presented. The goals of the work are to obtain eigenexpressions for calculating the numerical values of the Gibbs free energy depending on temperature using tabulated values of the standard enthalpies of formation and entropies of inorganic substances, as well as to construct graphical dependences of the Gibbs energy on temperature using formulas from literary sources and obtained expressions. Numerical values of the boundary temperatures are obtained above which the chemical reactions of the stepwise reduction of manganese from its dioxide by CO gas and the chemical reaction of gasification of solid carbon (Bella-Boudoir) can or cannot thermodynamically proceed. Considering the complete coincidence of the obtained data on the own (obtained) expressions using two (direct and indirect) methods, it is possible to consider with a significant degree of probability the numerical values of the boundary temperature for the reactions of stepwise reduction of manganese from its dioxide and gasification of solid carbon as reliable, which indicates the possibility of the reduction of Mn2O3 from MnO2, Mn3O4 from Mn2O3 and MnO from Mn3O4 by CO gas, the Bell-Boudoir reaction and the impossibility of the reduction of manganese from MnO by CO gas at the temperatures of the actual process in reduction furnaces. This also confirms that CO gas is not a manganese reducer at the last stage of stepwise reduction of MnO according to scheme (B), refuting any theories and assumptions about the possibility of reducing Mn from MnO by CO gas.