Methods and systems for removing polar compounds from a metal-containing solution

Abstract

Methods and systems for removing polar compounds from a metal-containing solution. According to various example aspects, methods and systems for removing hydrolysis byproducts and other polar compounds from a metal-loaded organic solution of a solvent extraction process.

1 . A method of recovering metal from a metal-containing aqueous solution, comprising
 contacting an aqueous solution comprising a metal with an organic solution to extract a portion of the metal into the organic solution and forming a metal-loaded organic solution comprising polar compounds and a metal-depleted aqueous solution;   separating the metal-loaded organic solution from the metal-depleted aqueous solution;   removing a portion of the polar compounds from the metal-loaded organic solution by contacting the metal-loaded organic solution with a polar solid to adsorb the polar compounds onto the polar solid and forming a treated metal organic solution; and   recovering metal values from the treated metal organic solution.   
     
     
         2 . The method of  claim 1 , wherein removing further comprises
 contacting the metal-loaded organic solution with a clay prior to the contacting with the polar solid.   
     
     
         3 . The method of  claim 1 , wherein the metal values are selected from a group consisting of copper, iron, nickel, zinc, metal alloys thereof and combinations thereof. 
     
     
         4 . The method of  claim 1 , wherein the organic solution comprises a water immiscible solvent and a reagent selected from a group consisting of a ketoxime, an aldoxime and combinations thereof. 
     
     
         5 . The method of  claim 1 , wherein the water immiscible solvent is selected from a group consisting of kerosene, benzene, toluene, xylene and combinations thereof. 
     
     
         6 . The method of any of  claims 1  to  5 , wherein the organic solution comprises a phenolic oxime. 
     
     
         7 . The method of  claim 6 , wherein a concentration of the phenolic oxime in the organic solution is about 0.018 M to about 1.1 M. 
     
     
         8 . The method of  claim 6 , wherein the phenolic oxime is a ketoxime or an aldoxime at a concentration of about 0.018 M to about 0.9 M. 
     
     
         9 . The method of any of  claims 1  to  5 , wherein the organic solution comprises 3-methyl ketoxime, 3-methyl aldoxime, 2-hydroxy-5-nonylacetophenone, 5-nonylsalicylaldoxime, 5-dodecylsalicylaldoxime, or a combinations thereof. 
     
     
         10 . The method of any of  claims 1  to  5 , wherein the organic solution comprises a 3-methyl ketoxime and a 3-methyl aldoxime in a molar ratio of about 85:15 to about 25:75. 
     
     
         11 . The method of any of  claims 1  to  5 , wherein the polar compounds comprise phenolic oximes and oxime hydrolysis byproducts. 
     
     
         12 . The method of  claim 11 , wherein the oxime hydrolysis byproducts comprise ketone compounds, aldehyde compounds and combinations thereof. 
     
     
         13 . The method of any of  claims 1  to  5 , wherein contacting the aqueous solution with the organic solution and separating the metal-loaded organic solution from the metal-depleted aqueous solution is via a solvent extraction process. 
     
     
         14 . The method of any of  claims 1  to  5 , wherein removing a portion of the polar compounds from the metal-loaded organic solution comprises, passing a bleed stream from a main stream of the metal-loaded organic solution through the polar solid and passing the treated metal organic solution to the main stream. 
     
     
         15 . The method of  claim 1  or  13 , further comprising
 measuring one or more parameter of the metal-loaded organic solution and of the treated metal organic solution and adjusting a flow rate through the polar solid based on the measured parameter. 
 
     
     
         16 . The method of any of  claims 1  to  5 , wherein the polar solid is comprised in a low-pressure column or a pressure column. 
     
     
         17 . The method of any of  claims 1  to  5 , wherein the polar solid comprises a material selected from a group consisting of silica, alumina, activated carbon and combinations thereof. 
     
     
         18 . The method of any of  claims 1  to  5 , wherein the polar solid comprises silica. 
     
     
         19 . The method of any of  claims 1  to  5 , further comprising
 regenerating the polar solid to remove adsorbed polar compounds by contacting the polar solid with a polar solvent. 
 
     
     
         20 . A method for removing polar compounds from a solution, comprising
 contacting an organic solution comprising non-polar metal complexes and polar compounds with a polar solid and adsorbing the polar compounds onto the polar solid.