Anode chronopotentiometry was used to study dissolved Al in cryolite melts, and the kinetics of the anode process. The estimated values of the diffusion coefficients (table 200) were found to be anomalously large. In addition to the usual translational diffusion mechanism, an additional mechanism which was related to electron jumps seemed to be operating.
M.M.Vetyukov, B.S.Dyblin: Elektrokhimiya, 1975, 11[3], 504-6
Table 200
Diffusivity of Al in Molten Cryolite Containing 5wt%Al2O3
Temperature (C) | D (cm2/s) |
995 | 4.902 x 10-4 |
1007 | 4.850 x 10-4 |
1018 | 5.180 x 10-4 |
1044 | 6.630 x 10-4 |
1072 | 7.900 x 10-4 |