| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method in which a copper-containing acid waste liquid such as a copper chloride-containing etching waste liquid and the renewal waste liquid of an electrolytic copper foil plating bath which have been disposed of as industrial waste is disposed of without requiring complicated equipment, and copper oxide having a low chlorine content is recovered from the copper-containing acid waste liquid. <P>SOLUTION: In the method for recovering copper, a mixed liquid of a copper-containing acid waste liquid with an oxidizing agent is added to the inside of a mixing reaction tank fed with a prescribed amount of alkaline solution while performing control in such a manner that the pH of the liquid in the mixing reaction tank is not reduced to≤9 even if it is temporarily, mixing is performed, an alkaline suspension comprising solid matter essentially consisting of copper oxide is produced, and the solid matter is separated from the inside of the alkaline suspension, at the point of time in which the addition amount of the mixed liquid exceeds at least 0.5 equivalent the amount of the copper-containing acid waste liquid required for neutralizing the alkaline solution in the mixing reaction tank, while intermittently performing the addition of the mixed liquid to the inside of the mixing reaction tank, the downtime of the addition is controlled to≥10 min. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
