Process for optimizing the process of copper electro-winning and electro-refining by superimposing a sinusoidal current over a continuous current

Abstract

This invention discloses a process of the electro-winning of metals, in particular copper, is done in a strongly acidic aqueous solution (˜180 gpl H 2 SO 4 ), with permanent cathodes of stainless steel or Cu starting sheets, and Pb—Ca—Sn anodes, in tradition electrolysis cells to obtain copper cathodes wherein in the electrolytic cells, a sinusoidal current is super-imposed over the continuous current in order to produce high-purity electrolytic copper. This invention also discloses the electro-refining process of metals, in particular copper, is done in a strongly acidic aqueous solution (˜180 gpl H 2 SO 4 ), with permanent cathodes of stainless steel or Cu starting sheets, and anodes of impure copper from founding, in traditional electrolysis cells in order to obtain copper cathodes wherein in the electrolytic cells, a sinusoidal current is super-imposed over the continuous current in order to produce high-purity electrolytic copper.

1 . A method for electro-winning of metals, the method comprising:
 in electrolytic cells with permanent cathodes of stainless steel or Cu starting sheets, Pb—Ca—Sn anodes, and an acidic aqueous solution comprising approximately 180 gpl H 2 SO 4 , superimposing a sinusoidal current over a non-zero continuous offset current to produce high-purity electrolytic copper.   
     
     
         2 . A method for electro-refining of metals, the method comprising:
 in electrolytic cells with permanent cathodes of stainless steel or Cu starting sheets, anodes of impure copper from founding, and an acidic aqueous solution comprising approximately 180 gpl H 2 SO 4  superimposing a sinusoidal current over a non-zero continuous offset current to produce high-purity electrolytic copper.   
     
     
         3 . The method according to  claim 1 , wherein the sinusoidal current applied in the electrolytic cells has an amplitude greater than 400 A/m 2  and a frequency greater than 1,000 Hz. 
     
     
         4 . The method according to  claim 2 , wherein the sinusoidal current applied in the electrolytic cells has an amplitude greater than 400 A/m 2  and a frequency greater than 1,000 Hz. 
     
     
         5 . The method according to  claim 1 , wherein the solution entering the cells operates with temperatures less than 40° C., with Cu 2+  concentrations less than 30 gpl, and with flows less than 240 l/min/cell when an amplitude of the sinusoidal current at a continuous offset current of greater than or equal to 300 A/m 2 . 
     
     
         6 . The method according to  claim 2 , wherein externally manipulated operating variables are established in function of amplitude and frequency of the sinusoidal current super-imposed over a continuous offset current greater than or equal to 300 A/m 2 .