Adsorption of Freon 113

Summary The adsorption of Freon 113 (1,1,2 trichloro-1,2,2 trifluoroethane) at 260–310 K on Graphon was measured and compared with the adsorption of krypton at 104–120 K on the same surface. The adsorption isotherms, and resulting thermodynamics, for both adsorbates were similar over the entire pressure range studied. Surface area analysis of the data suggests that the Freon molecule occupies approximately 2.5 times the area of the krypton molecule on Graphon. Further, the Freon molecules are hindered in their rotational freedom on this surface at these temperatures, with their dipole axes aligning perpendicular to the surface of the Graphon.

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Zusammenfassung Es wurde die Adsorption von Freon 113 (1,1,2 Trichlor-1,2,2 Trifluoräthan) an Graphon bei 260–310 °K gemessen und mit der Adsorption von Krypton bei 104–120 °K auf der gleichen Grenzfläche gemessen. Die Adsorptionsisothermen und die daraus resultierenden thermodynamischen Daten waren für beide Adsorbate im gesamten untersuchten Druckbereich ähnlich. Eine Analyse der Daten legt nahe, daß ein Freonmolekiil annähernd das 2,5fache der Fläche eines Kryptonmoleküls auf Graphon beansprucht. Es ist anzunehmen, daß die Freonmoleküle auf dieser Oberfläche und bei diesen Temperaturen in ihren Rotationsfreiheitsgraden gehindert sind und ihre Dipolachsen senkrecht zur Oberfläche liegen.

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With 9 figures and 2 tables     

Species selective evaporation during surface scattering of binary van der Waals clusters

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