Three transition times were observed during the chronopotentiometric study of CoCl2 in fused alkali chloride solutions. The first and third times were diffusion-controlled and did not coexist. The third was most obvious in equimolecular NaCl-KCl mixtures at 700C. It was believed to be due to the discharge of CoCl42-. The second transition time was related to a process which was not completely diffusion-controlled, and which probably involved the discharge of CoCl3-. The diffusion coefficients which were calculated from the chronopotentiometric data were smaller than those predicted from theoretical formulae by using the radius of Co2+. This behavior was attributed to the fact that Co2+ was not the ion which was being diffused (table 83).

Y.K.Delimarskii, V.F.Grishchenko, N.I.Parkhomenko: Ukrainski Khimicheski Zhurnal, 1975, 41[11], 1123-7

 

Table 85

Diffusivity of Ni Ions in Molten KCl-NaCl

 

Temperature (C)

NiCl2 (/cm3)

D (cm2/s)

705

1.02 x 105

2.69 x 10-5

705

2.00 x 105

2.20 x 10-5

705

2.05 x 105

2.36 x 10-5

705

0.99 x 105

2.18 x 10-5

807

1.96 x 105

3.18 x 10-5

807

2.00 x 105

2.88 x 10-5

807

2.00 x 105

2.56 x 10-5