SEPARATION OF METAL

PURPOSE:To produce fine metal powder with no need for secondary crushing by dipping a solid metal in an aq. soln. of the salts of metals having an electric potential nobler than the solid metal, and applying ultrasonic vibration at the time of depositing the metal from the metallic salts by electrolytically replaced method. CONSTITUTION:When fine Cu powder is produced by electrolytically replaced method, for example, an aq. soln. of CuSO4.5H2O is introduced into a metallic vessel of stainless steel, etc., a solid piece of the Fe having a potential baser than the Cu is dipped in the soln., and ultrasonic vibration at >=20kHz is applied to the solid piece of the Fe. The metallic Cu is deposited on the Fe piece, and immediately released in the form of fine powder by the ultrasonic vibration. As a result, fine Cu powder having a narrow distribution of particle size is obtained without using a secondary crushing means.