Method of extracting platinum group metals from waste catalysts through electrochemical process

Abstract

A method of extracting platinum group metals from waste catalysts through an electrochemical process is disclosed. The extracting method includes positioning the waste catalysts between both electrodes in an electrolytic cell, leaching the platinum group metals as regularly changing polarities of the electrodes to each other, and precipitating the platinum group metals on a cathode by circulating the electrolyte from an anode to a cathode. According to the method, the platinum group metals can be extracted with high efficiency and high yield. Also, the extracting process is simplified to remarkably reduce costs required to extract the platinum group metals.

1 . A method of extracting platinum group metals from waste catalysts through an electrochemical process, the method comprising: positioning the waste catalysts between both electrodes in an electrolytic cell; leaching the platinum group metals as regularly changing polarities of the electrodes to each other; and precipitating the platinum group metals on a cathode by circulating an electrolyte from an anode to a cathode. 
   
   
       2 . The method as claimed in  claim 1 , wherein the electrolyte generates chlorine anions. 
   
   
       3 . The method as claimed in  claim 1 , wherein the electrolyte is a solution of 0.3 to 10.0% hydrochloric acid. 
   
   
       4 . The method as claimed in  claim 1 , wherein a current density is 0.006 A/cm 2  to 0.025 A/cm 2  at electrochemical sedimentation. 
   
   
       5 . The method as claimed in  claim 1 , wherein the electrochemical leaching is activated by multi-pole reverse electrodes in a state that the electrodes are transformed into multi-pole electrodes that can cause anodic dissolution of all metal materials. 
   
   
       6 . The method as claimed in  claim 1 , wherein the electrolyte is circulated from the anode to the cathode at a speed enough to prevent hydrated anionic chloride complexes of the precious metals from being drifted on the cathode.