Details

Autor(en) / Beteiligte

• Kravchenko, A. I.
• Zhukov, A. I.

Titel

Separation Factors and Peclet Numbers in Evaporation Refining of Elemental Substances near Their Melting Point

Ist Teil von

• Inorganic materials, 2022-08, Vol.58 (8), p.860-865

Ort / Verlag

Moscow: Pleiades Publishing

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• — Using the Burton–Prim–Slichter equation, we demonstrate that distillation or sublimation refining of some elemental substances (as exemplified by Sm, Yb, Mg, Eu, Te, Zn, Cd, Be, and Tb) at T = (0.9–1.2) T m (where T m is the melting point) can degrade with increasing temperature as a consequence of the increase in the effective separation factor, β < 1, and/or the increase in the diffusional Peclet number Pe = wX /ρ D (where w is the substance vaporization rate per unit area, D is the impurity diffusion coefficient, ρ is the density of the substance, and X is a size factor of the material being evaporated), the particular effect of β or Pe being dependent on the nature of the host and impurities. In addition, we demonstrate that Pe is small in crystallization refining processes, so the main process parameter is the separation factor.