Study of the dependence of radiation resistance of diesel fuel on its chemical structure

The radiation stability of petroleum-derived fuels is an important consideration for their use under ionizing-radiation conditions, where radiation-induced chemical transformations may affect their physicochemical and operational properties. In this study, the effect of naphthalene as an aromatic additive on the radiation resistance and post-irradiation behavior of diesel fuel was investigated under ^60Co γ-irradiation. Diesel fuel containing 0.2, 0.4, 0.6, and 1.0 wt% naphthalene was irradiated at absorbed doses ranging from 21 to 64 kGy. Changes in density, kinematic viscosity, ignition-related properties, and chemical composition were evaluated immediately after irradiation and during subsequent storage for up to 8 months. The results indicate that irradiation induces measurable changes in the physicochemical properties of diesel fuel, while the extent of these changes depends on both absorbed dose and naphthalene concentration. The addition of naphthalene, particularly at concentrations of 0.6–1.0 wt%, reduced the magnitude of post-irradiation changes, suggesting a stabilizing effect of the aromatic additive. The observed behavior is consistent with the involvement of radical stabilization and energy-transfer processes associated with the aromatic π-electron system of naphthalene. These findings demon strate that fuel composition plays an important role in determining the radiation-induced and post-irradiation behavior of diesel fuel.