| 摘要 |
<p>PROBLEM TO BE SOLVED: To recover high purity copper or a copper alloy from a heat exchanger consisting of aluminum fin parts and copper pipe parts, of an abandoned air-conditioner. SOLUTION: This method comprises: crushing such a heat exchanger into a small fragment mixture in which small aluminum fragments and small copper fragments, each formed as a separate fragment from the other, coexist; selectively separating the copper fragments from the fragment mixture; and washing the separated copper fragments having >=0.02 g average copper fragment mass, with an alkali solution whose pH and temperature are >=12 and 20-95 deg.C respectively, to dissolve and remove aluminum stuck to the surface of each of the copper fragments.</p> |
