Table 2. Values of Crystallization Tates k1 and k2 Obtained by Fitting the Turbidity Profiles to a JMAK Modela.
| concentration
(mM) |
||||||||
|---|---|---|---|---|---|---|---|---|
| k (×10–3 s–1) | 0 | 0.06 | 0.1 | 0.15 | 0.2 | 0.25 | 0.3 | |
| La | k1 | 9.006 | 5.251 | 4.268 | 5.481 | 5.223 | 1.784 | 1.737 |
| k2 | 8.091 | 6.208 | 5.816 | 5.481 | 4.790 | 4.423 | 4.404 | |
| Nd | k1 | 9.006 | 5.382 | 4.121 | 1.913 | 2.308 | 0.485 | 2.088 |
| k2 | 8.091 | 5.365 | 4.858 | 3.889 | 3.224 | 2.407 | 1.815 | |
| Dy | k1 | 9.006 | 5.459 | 1.838 | 2.194 | 1.982 | 1.396 | 0.661 |
| k2 | 8.091 | 6.011 | 5.167 | 4.651 | 4.632 | 4.152 | 3.494 | |
| LaNd | k1 | 9.006 | 6.044 | 8.478 | 5.572 | 5.733 | 3.958 | 4.391 |
| k2 | 8.091 | 7.158 | 8.240 | 6.827 | 6.533 | 6.055 | 5.426 | |
| LaDy | k1 | 9.006 | 8.665 | 5.090 | 0.566 | 1.808 | 1.107 | 0.343 |
| k2 | 8.091 | 7.839 | 6.026 | 6.252 | 5.270 | 4.582 | 3.217 | |
| NdDy | k1 | 9.006 | 7.799 | 6.792 | 3.105 | 4.160 | 1.576 | 0.170 |
| k2 | 8.091 | 7.667 | 6.629 | 5.033 | 4.907 | 3.411 | 2.623 | |
| LaNdDy | k1 | 9.006 | 8.189 | 7.381 | 6.819 | 3.673 | 3.508 | 2.418 |
| k2 | 8.091 | 8.110 | 7.384 | 7.265 | 5.425 | 4.621 | 3.870 | |
a
Each turbidity profile fits to this model using two n and k values. The first n and k values correspond to the initial part of the turbidity profiles (α ≃ 0–0.07) while the second correspond to the main part of the turbidity profile up to the end of the primary crystallization reaction (α ≃ 0.07–1). The indicated concentration in solutions containing multiple REEs refers to the total combined concentration of REEs.