| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a purification method for simply and efficiently removing chromium, preferably vanadium together with chromium contained in a tungsten-containing alkali solution. <P>SOLUTION: The method for purifying a tungsten-containing alkali solution is characterized in that chromium and/or vanadium is removed, by adding a divalent iron compound to the tungsten-containing alkali solution including the chromium and/or vanadium and by separating a formed precipitate by filtration. Ferrous sulfate, ferrous acetate or ferrous formate is preferably used as the divalent iron compound and a precipitate is preferably formed after adjusting the pH of the alkali solution to 8-13. <P>COPYRIGHT: (C)2013,JPO&INPIT |
