Reduction of copper content in the molybdenite concentrate

Abstract

Methods and systems for removing copper minerals from a molybdenite concentrate. One embodiment provides leaching copper from the molybdenite concentrate with a leaching solution comprising ferric chloride, removing molybdenite from the leaching solution, introducing an acid into the leaching solution and introducing O 2 , O 3 , or a combination of both, into the leaching solution. A method for regenerating ferric chloride in a leaching solution is also provided. One embodiment provides adding a leaching solution comprising Fe(II) ions, Fe(III) ions, or a combination of both, to a mixture of mineral sulfides, introducing an acid into the leaching solution, and introducing O 2 , O 3 , or a combination of both, into the leaching solution.

1 . A method for removing copper sulfides from a molybdenite concentrate, the method comprising: 
 a) leaching the copper sulfides from the molybdenite concentrate with a leaching solution comprising ferric chloride;    b) introducing an acid into the leaching solution; and    c) introducing O 2 , O 3  or a combination of both, into the leaching solution.    
   
   
       2 . The method of  claim 1 , further comprising separating the molybdenite concentrate from a copper ore prior to leaching the copper sulfides from the molybdenite concentrate.  
   
   
       3 . The method of  claim 1 , further comprising removing molybdenite from the leaching solution by filtration.  
   
   
       4 . The method of  claim 1 , wherein the leaching process is performed in a batch operation mode.  
   
   
       5 . The method of  claim 1 , wherein the leaching process is performed in a continuous operation mode.  
   
   
       6 . The method of  claim 1 , wherein the acid comprises hydrochloric acid.  
   
   
       7 . The method of  claim 6 , wherein the hydrochloric acid is kept at a concentration between about 1.0 M and about 4.0 M.  
   
   
       8 . The method of  claim 1 , wherein the leaching solution maintains a leached copper ion concentration above about 1 g/L.  
   
   
       9 . The method of  claim 1 , wherein the leaching solution is maintained at a temperature above about 90° C.  
   
   
       10 . The method of  claim 1 , wherein the leaching solution is maintained in a vessel at a pressure between about 0 and about 30 bar gauge compared to atmospheric pressure during the introducing O 2 , O 3  or a combination of both.  
   
   
       11 . The method of  claim 1  further comprising agitating the leaching solution for between about 10 minutes to about 120 minutes during the introducing O 2 , O 3  or a combination of both.  
   
   
       12 . The method of  claim 1 , further comprising removing copper from the leaching solution by exposure to scrap iron.  
   
   
       13 . The method of  claim 1 , wherein the molybdenite concentrate comprises copper in a concentration of less than 0.2% w/w after leaching copper from the molybdenite concentrate.  
   
   
       14 . A method for obtaining commercial grade molybdenite from a copper ore, the method comprising: 
 a) separating a molybdenite concentrate from the copper ore;    b) leaching copper from the molybdenite concentrate with a leaching solution comprising ferric chloride;    c) removing molybdenite from the leaching solution;    d) introducing an acid into the leaching solution; and    e) introducing O 2 , O 3  or a combination of both, into the leaching solution.    
   
   
       15 . The method of  claim 14 , wherein the removing of molybdenite from the leaching solution comprises filtration.  
   
   
       16 . The method of  claim 14 , wherein the leaching process is performed in a batch operation mode.  
   
   
       17 . The method of  claim 14 , wherein the leaching process is performed in a continuous operation mode.  
   
   
       18 . The method of  claim 14 , wherein the acid comprises hydrochloric acid.  
   
   
       19 . The method of  claim 18 , wherein the hydrochloric acid is kept at a concentration between about 1.0 M and about 4.0 M.  
   
   
       20 . The method of  claim 14 , wherein the leaching solution maintains a leached copper ion concentration above about 1 g/L.  
   
   
       21 . The method of  claim 14 , wherein the leaching solution is maintained at a temperature above about 90° C.  
   
   
       22 . The method of  claim 14 , wherein the leaching solution is maintained in a vessel at a pressure between about 0 and about 30 bar gauge compared to atmospheric pressure during the introducing O 2 , O 3 , or a combination of both.  
   
   
       23 . The method of  claim 14  further comprising agitating the leaching solution for between about 10 minutes to about 120 minutes during the introducing O 2 , O 3  or a combination of both.  
   
   
       24 . The method of  claim 14 , further comprising removing copper from the leaching solution by exposure to scrap iron.  
   
   
       25 . The method of  claim 14 , wherein the molybdenite concentrate comprises copper in a concentration of less than 0.2% w/w after leaching copper from the molybdenite concentrate.  
   
   
       26 . A method for removing copper sulfides from a molybdenite concentrate, the method comprising: 
 a) pumping the molybdenite concentrate into an autoclave vessel;    b) introducing a solution comprising Fe(II) ions, Fe(III) ions, or a combination of both, into the autoclave vessel;    c) introducing an acid into the autoclave vessel;    d) introducing O 2 , O 3  or a combination of both, into the autoclave vessel; and    e) filtering the molybdenite from a stream exiting the autoclave vessel.    
   
   
       27 . The method of  claim 26 , wherein the autoclave vessel maintains a pressure between about 0 and about 30 bar gauge compared to atmospheric pressure.  
   
   
       28 . The method of  claim 26 , wherein the Fe(II) ions comprise ferrous chloride and the Fe(III) ions comprise ferric chloride.  
   
   
       29 . The method of  claim 26 , wherein the acid comprises hydrochloric acid.  
   
   
       30 . The method of  claim 29 , wherein the hydrochloric acid is kept at a concentration between about 0.5 M and about 4.0 M in the autoclave vessel.  
   
   
       31 . The method of  claim 26 , wherein the solution maintains a leached copper ion concentration above about 1 g/L.  
   
   
       32 . The method of  claim 26 , wherein the solution and molybdenite concentrate are maintained at a temperature between about 100° C. and about 120° C. in the autoclave vessel.  
   
   
       33 . The method of  claim 26 , further comprising providing agitation in the autoclave vessel for between about 10 minutes and about 120 minutes.  
   
   
       34 . The method of  claim 26  further comprising: 
 f) chemically reducing copper ions in the solution to elemental copper by exposing the solution to iron; and    g) moving elemental copper.    
   
   
       35 . The method of  claim 26 , wherein the molybdenite concentrate comprises copper in a concentration of between about 3% w/w and 5% w/w before entering the autoclave vessel, and wherein the molybdenite comprises copper in a concentration of less than 0.2% w/w after the filtering of the molybdenite.  
   
   
       36 . A method for regenerating ferric chloride in a leaching solution, the method comprising: 
 a) adding a leaching solution comprising Fe(II) ions, Fe(III) ions, or a combination of both, to a mixture of mineral sulfides;    b) introducing an acid into the leaching solution; and    c) introducing O 2 , O 3  or a combination of both, into the leaching solution; whereby ferric chloride is regenerated.    
   
   
       37 . The method of  claim 36 , wherein the leaching process is performed in a batch operation mode.  
   
   
       38 . The method of  claim 37 , wherein the leaching process is performed in a continuous operation mode.