| 摘要 |
PURPOSE:To obtain high purity FeCl2 by adding hydrochloric acid to a FeCl2 soln. contg. metal impurities and by separating FeCl2 crystals deposited. CONSTITUTION:Iron or a metal baser than iron is added to a FeCl3 soln. contg. impurities such as FeCl2, CuCl2 and NiCl2 used to etch a printed wiring plate, reducing the FeCl3 to FeCl2 by a usual method. While maintaining the concn. of the resulting FeCl2 soln. at 5-38wt%, hydrochloric acid is added to adjust the concn. of hydrochloric acid in the soln. to 8-32%, and FeCl2 crystals deposited are separated to obtain high purity FeCl2. The separated mother liquor is heat treated to recover hydrochloric acid, and the liquor is disposed after forming iron oxide and oxides of impurity metals with an alkali substance and air. |
