Comparative Analysis of Explosion and Toxic Dispersion Ranges of Xylene Isomers According to Physicochemical Properties

In this study, we quantitatively analyze the explosion and toxic dispersion ranges of three common isomers of xylene (o-, m-, and p-xylene) that are widely used in industrial applications with regard to variations in their physicochemical properties. Previous studies on chemical accident risks could not fully consider subtle differences among xylene isomers because they treated xylene as a single substance. We address this limitation by providing foundational data to develop more precise chemical accident response measures. The dispersion of hazardous substances was simulated using a hazard modeling program provided by the US Environmental Protection Agency called ALOHA to analyze the characteristics of each isomer. Explosion and toxic release scenarios were designed with the boiling points and vapor pressures of each isomer as key property values. The differences among the isomers were compared by calculating the overpressure damage range in an explosion scenario and the toxic dispersion distance in a release scenario. The results of the analysis show that all three isomers exhibited similar overpressure damage ranges in the explosion scenario. This indicates that subtle differences in properties such as boiling point and vapor pressure are not fully reflected in explosion energy because an explosion is an instantaneous reaction that occurs within a short period of time. In the release scenario, however, m-xylene exhibited a wider toxic dispersion range than the other isomers. This is attributed to the relatively high vapor pressure and rate of vaporization, which indicates that additional safety management measures are required while handling m-xylene. Our findings highlight that the physicochemical properties of each isomer should be considered beyond the existing practice of treating xylene as a single substance in established chemical accident response plans. These results also contribute to a more precise prediction of accidents and to the development of safety management strategies.