Refinement of data on the volatility of octavalent plutonium in the form of tetraoxide PuO4

The previous determinations 1–5] of the enthalpy of adsorption of PuO₄ on the quartz surface, which was calculated with an error of ±6 kJ mol^?1, are insufficiently accurate. Gas thermochromatographic experiments aimed to refine the temperature of PuO₄ deposition under definite temperature and gas-dynamic conditions were performed. The carrier gas was an He-O₂ mixture (1: 1). From the data obtained, more correct value of ?δH _a ⁰ was calculated: 43 ± 4 kJ mol^?1. The standard enthalpy of sublimation δH _{298, subl} ⁰ of PuO₄ was estimated at 35 ± 10 kJ mol^?1 using the linear correlation between the enthalpies of adsorption and sublimation of transition metal oxides.