| 摘要 |
A method for preparing a mixture of rare-earth elements is provided to extract and separate rare earth elements from igneous rocks at a low cost, and to widen a physical property range of a useful component at a low energy cost. A method for preparing a mixture of rare-earth elements containing natural radioactive nuclei from granodiorite includes the steps of: grinding the granodiorite into powder(40 micron or smaller), mixing the powder with distilled water to obtain a saturated aqueous solution, dispersing the solid particles sufficiently using a homogenizer, and performing dispersion and breaking to obtain the saturated aqueous solution having a particle size of 10 micron or smaller; and cooling the saturated aqueous solution, sublimating water by a low-temperature drying method, dry-breaking the resultant to obtain recrystallized powder, re-saturating the fine powder with distilled water, stirring the re-saturated solution for 120 minutes or more using an ultrasonic homogenizer of 20 Kh, removing all water, adding diethylenetriaminepentaacetate to the resultant, sonicating the admixture to obtain a filtrate, centrifuging the filtrate to separate out SiO2 and clay, collecting floating particles, and performing a specific gravity sorting method and a wet magnetic force sorting method at the same time. |
