The chronopotentiometric method was used to study the effect of temperature and alumina content upon the diffusion of Al and Na sub-ions, in the form of AlF and Na2F. The diffusivity decreased with increasing alumina content: slightly from 1 to 6%, and markedly above 6% (table 172).
M.M.Vetyukov, A.Z.Saber, Y.V.Borisoglebskii, L.V.Krylov: Izv. Vyssh. Uchebn. Zaved., Tsvetn. Metall., 1978, 4, 62-4
Table 173
Self-Diffusion of 18F in Molten Na3AlF6-Al2O3 Mixtures
Al2O3 (%) | Temperature (C) | D (cm2/s) |
0 | 1034.0 | 5.70 x 10-5 |
0 | 1045.5 | 5.86 x 10-5 |
0 | 1052.0 | 5.81 x 10-5 |
0 | 1065.0 | 6.10 x 10-5 |
12.9 | 1052.5 | 3.81 x 10-5 |