| 摘要 |
<p>A process for producing an ultra pure fluoride product salt of a metal selected from Zr, Hf, Ba, La, Al and Na, including recrystallizing from aqueous media a soluble precursor salt material containing one or more of Fe, Ni, Cu, Co, Ce, Nd or Sm impurities, the precursor salt material being selected from the chlorides, bromides, iodides, oxychlorides, oxybromides, oxyiodides, nitrates and oxynitrates of the metals, the recrystallization including the steps of essentially completely solubilizing the precursor salt material and any of the impurities present through adjustment of temperature and/or acidity of the aqueous media, and thereafter completely insolubilizing essentially only the precursor salt through readjustment of the temperature and/or acidity to leave the impurities in the media, and separating the purified precursor salt from the media, fluorinating the purified precursor salt with a fluorinating agent at a temperature of from about 0 to about 100 degrees C, to yield a substantially insoluble purified fluoride product salt in contact with a liquor containing the combined impurity content of the purified precursor salt and the fluorinating agent, and isolating the purified fluoride product salt from the liquor.</p> |
