| 摘要 |
<p>A process for the treatment of tri(alkaline earth metal) tungstates, especially tricalcium tungstate, with organic amines is disclosed. The tungstate is contacted with an aqueous solution of the organic amine that also contains carbonate and/or bicarbonate anions in a concentration such that compounds of the anion and the alkaline earth metal are less soluble in the solution than the tungstate of the alkaline earth metal. Representative organic amines are piperidine, diethanolamine, hexamethylene diamine, monoethylamine and dimethylamine. The process is useful in the extraction of tungsten from ores.</p> |
