The capillary reservoir technique was used to study the diffusion of 22Na in molten mixtures (table 180). It was suggested that AlF63-, AlF4-, NaF and Na2F+ complexes were present in the melt. The activation energy for 22Na diffusion in samples with 13.5mol%AlF3, at temperatures ranging from 938 to 1070C, was 9.5kcal/mol. The activation energy for diffusion in samples with 37.5mol%AlF3, at 928 to 999.7C, was 7.0kcal/mol. Na-22 and F-18 Diffusion in Na and Al Fluoride Baths. D.Harari, F.Lantelme, M.Chemla: Journal de Chimie Physique et de Physicochimie Biologique, 1969, 66[7-8], 1286-91

 

Table 180

Self-Diffusion of 22Na in NaF-AlF3 Melts

 

AlF3 (mol%)

Temperature (C)

D (cm2/s)

0

1049

9.80 x 10-5

0

1052

1.00 x 10-4

13.5

938

6.82 x 10-5

13.5

944.5

7.65 x 10-5

13.5

1012

8.17 x 10-5

13.5

1051

1.06 x 10-4

13.5

1070

1.03 x 10-4

25.0

1048

9.30 x 10-5

25.0

1049.5

9.44 x 10-5

25.0

1054

9.36 x 10-5

37.5

928

8.31 x 10-5

37.5

941

8.05 x 10-5

37.5

968.5

9.39 x 10-5

37.5

999.7

1.02 x 10-4