| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method capable of efficiently recovering cerium from chromium etching solution containing cerium compound and chromium compound. <P>SOLUTION: The chromium etching solution is vaporized and concentrated and the cerium compond is crystallized, separated and recovered and also, the cerium in the separated solution after separating the cerium compound, is separated and recovered as oxalate. Into the solution containing trivalent chromium after separating the oxalate of trivalent cerium, an alkaline hydroxide is added and the trivalent chromium is precipitated as chromium hydroxide and separated to constitute a closed system. <P>COPYRIGHT: (C)2004,JPO</p> |
