Liquid-liquid extraction of germanium from aqueous solution using hydroxy-oximes

Abstract

Process for extraction of germanium from aqueous acid solution by contacting with an organic liquid containing a hydroxy-oxime and recovering the extracted germanium from the organic phase.

What we claim is: 
     
       1. A process for liquid-liquid extraction of germanium from an aqueous solution, in which an organic liquid containing .[.hydroxy-oxime.]. .Iadd.α-hydroxy-oxime .Iaddend.is used as extractant comprising contacting an aqueous solution containing germanium and an acid selected from the group consisting of 10 to 500 grams per liter of hydrochloric acid, 10 to 500 grams per liter of sulfuric acid, and 10 to 100 grams per liter of hydrofluoric acid, with an organic liquid selected from the group consisting of non-diluted .[.hydroxy-oxime.]. .Iadd.α-hydroxy-oxime.Iaddend., a solution of .[.hydroxy-oxime.]. .Iadd.α-hydroxy-oxime .Iaddend.in an aliphatic solvent, a solution of .[.hydroxy-oxime.]. .Iadd.α-hydroxy-oxime .Iaddend.in an aromatic solvent, and a solution of .[.hydroxy-oxime.]. .Iadd.α-hydroxy-oxime .Iaddend.in a mixture of an aliphatic and an aromatic solvent, separating the organic liquid phase containing extracted germanium from the residual aqueous phase, and recovering the extracted germanium from the separated organic phase by contacting with an agent selected from the group consisting of water, acids, and bases. 
     
     
       2. A process as claimed in claim 1, in which the aqueous solution contains 10 to 500 g/l of an acid chosen in the class consisting of sulfuric acid and hydrochloric acid. 
     
     
       3. A process as claimed in claim 1, in which the aqueous solution contains 10 to 100 g/l hydrofluoric acid. 
     
     
       4. A process as claimed in claim 1, in which a non-diluted hydroxy-oxime is used as the organic liquid. 
     
     
       5. A process as claimed in claim 1, in which a solution of a hydroxy-oxime in an aliphatic solvent is used as the organic liquid. 
     
     
       6. A process as claimed in claim 1, in which a solution of a hydroxy-oxime in an aromatic solvent is used as the organic liquid. 
     
     
       7. A process as claimed in claim 5, in which a higher alcohol is added to the hydroxy-oxime solution. 
     
     
       8. A process as claimed in claim 5, in which the organic liquid contains at least 1% by volume of a hydroxy-oxime. 
     
     
       9. A process as claimed in claim 6, in which the organic liquid contains up to 10% by volume of a higher alcohol. 
     
     
       10. A process as claimed in claim 1, in which 19-hydroxyhexatriaconta-9,28 diene-18-oxime is used as hydroxy-oxime. 
     
     
       11. A process as claimed in claim 5, in which kerosene is used as the solvent. 
     
     
       12. A process as claimed in claim 7, in which isodecanol is used as the higher alcohol. 
     
     
       13. A process as claimed in claim 1, in which the separated organic phase is regenerated by contacting it with a base, and is used again for another extraction. 
     
     
       14. A process as claimed in claim 13, in which use is made as a base of an aqueous solution of a compound selected from the group consisting of NaOH, KOH, limewash, magnesiawash, and ammonia. 
     
     
       15. A process as claimed in claim 1, in which the aqueous solution contains copper. 
     
     
       16. A process as claimed in claim 15, in which the separated organic phase is regenerated first by contacting it with a base in order to separate the germanium, and afterwards with an acid solution in order to separate the copper, and is used again for another extraction. .Iadd. 
     
     
       17.  A process as claimed in claim 1, in which 5,8-diethyl-7-hydroxydodecan-6-oxime is used as the α-hydroxy-oxime.