METHOD OF REGENERATING WASTE LIQUID OF COPPER ETCHING SOLUTION

摘要

PROBLEM TO BE SOLVED: To safely, efficiently and stably regenerate a waste liquid of a copper etching soln. containing sulfuric acid and hydrogen peroxide by bringing the copper etching waste liquid into contact with an oxime extracting agent to extract and remove copper. ;SOLUTION: The oxime extracting agent used is a cation exchange reaction type extracting agent which is effective to extract copper when the waste liquid is an acid soln. This extracting agent has selectivity for copper when other metal ions are present. The oxime extracting agent expressed by the formula is excellent because it shows high extracting performance for copper. In the formula, R₁, R₂ are each a hydrogen atom or hydrocarbon groups, and one of them has a hydroxyl group in the skeleton. The regenerated liquid having desired copper concn. obtd. by extraction is further preferably subjected to oil-water separation and to treatment with activated carbon. On the other hand, copper in the extracting agent waste liquid is removed by dissolving as copper sulfide in a sulfuric acid soln. which is a water phase, and the waste liquid can be reused as an extracting agent.;COPYRIGHT: (C)1999,JPO