- Fractional crystallization reduced the conductivity of commercial 90 w/o H2O2 (11.5 microohms-1 at 25 C) to approximately one-half (5.0 microohms-1 at 25 C) of its initial value, while increasing its concentration to 98+ w/o H2O2.
- Distillation of the crystallized H2O2 reduced its specific conductance to ~2 micromhos. This value compared with that reported in earlier studies.
- A second distillation of the crystallized and once distilled H2O2 reduced its specific conductance to 1.2 micromhos.
- The specific conductance of both 98 w/o H2O2 and de-ionized water increased on storage in contact with Pyrex glass. A conclusion of these studies indicated that only a rough correlation between low electrical conductivity and high stability was found (or that electrical conductivity per se is not a reliable indicator of stability).
Part of the Hydrogen Peroxide Propulsion Guide The electrical, magnetic, and electromagnetic (optical) properties of H2O2 have been grouped as electromagnetic properties. These properties are generally related to the electronic structure of the atoms in contrast to the transport properties which involve only molecular movement. Index of Refraction The data for propellant-grade H2O2-H2O solutions are presented in Table 2.15 at 25 C (77 F) with a temperature correction guide. Dipole Moment Calculated dipole moments of H2O2 were reported as 2.22 Debye (or 2.22 x 10-18 esu-cm) and 2.05 Debye respectively. In addition, a value of 2.26 Debye was estimated from the Stark effect, and a value of 2.13 Debye was determined for H2O2 in dioxane. The latter value was selected as the representative dipole moment for H2O2. Dielectric Constant Figures 2.23 and 2.23a show the dielectric constants of propellant-grade H2O2-H2O solutions as a function of temperature. These data were interpolated from the experimental studies reported in Ref. 2.39, in which the dielectric constants were determined as a function of composition at constant temperatures from -40 to 30 C (-40 to 86 F). Because of the supercooling of the H2O2-H2O solutions, measurements were obtained on the liquid below the freezing point. The data from the measurements on 100 w/o H2O2 were curve-fitted from -60 to 30 C (-76 to 86 F) to the following equation: € = 84.2 - 0.62 T(C) + 0.0032T(C)2 Electrical Conductivity The conductivity of "pure" H2O2 has been reported by several investigators with values ranging from 2 to 0.39 micromhos (microohms-1 ). Experimental studies of the conductivity of unstabilized H2O2 were conducted as a possible means of determining its purity. The results of this study are summarized as follows: