Oxidation Reaction Characteristics and Thermodynamic Analysis of Carbon Monoxide Following Gas Explosions.

The high concentration of CO generated in confined spaces following a gas explosion constitutes the primary lethal factor, and its rapid elimination represents a critical technical bottleneck in emergency rescue operations. This study systematically investigates the confined thermodynamic characteristics of CO catalytic oxidation over hopcalite across a wide temperature range of 15-65 °C. Based on the ideal gas assumption and constant-volume boundary conditions, the thermodynamic processes were classified into two categories: constant-volume variable-temperature and constant-temperature constant-volume. The influence of temperature on enthalpy change, heat release, entropy change, and the chemical equilibrium constant was quantitatively examined. The results demonstrate that the total enthalpy change and heat release remained negative throughout the entire temperature range, exhibiting a trend of "initial increase, subsequent decrease, followed by a slight rise", with the maximum exothermic value observed at 25 °C. The total entropy change was persistently negative across the full temperature range; the positive offset contribution of the physical entropy change induced by temperature elevation was negligible, resulting in a consistently high absolute value of the total entropy change. The logarithm of the standard equilibrium constant decreased linearly with increasing temperature yet remained as high as 180.48 at 65 °C, indicating that the reaction maintains an extremely strong thermodynamic spontaneity and a nearly complete conversion limit under all tested conditions.