Thermodynamic Analysis of Combustion Process in Oxide- and Peroxide-Salt Systems

Purpose. Determination of thermodynamic parameters of combustion reactions in solid-phase systems containing the salts of bivalent metals and sodium oxides Na2O, Na2O2, and NaO2. Methods. The methodology is based on the use of fundamental regulations of the chemical thermodynamics for determination of the energetic characteristics of the reactions. Results. After the analysis of interaction reactions of sodium oxide, peroxide, and superoxide with the salts of a number of bivalent metals, it is determined that the heat generation of the reactions and the temperature developed in the process of interaction determines their behavior in the combustion mode. The reaction heat and temperature in the reaction zone decrease in some cases of Na2O‒Na2O2‒NaO2. The temperature of burning of the salts with the sodium compounds diminishes in some cases of MeCl2‒MeSO4‒Me3(PO4)2‒Me(NO3)2. The combustion heat correlates with the potentials of the metal ionization generating the salts. Scientific novelty. Novel chemical reactions of oxide compounds of the alkaline metals with the salts of bivalent metals are proposed and their thermodynamic characteristics are determined. Practical value. Creation of autonomous chemical oxygen sources and heat-generating elements, synthesis of superparamagnetics and other functional ceramics, utilization of heavy metal salts and spent resource peroxide components of the individual and collective protective means of respiratory organs and atmosphere regeneration.