Extraction of noble metal (ions) by means of ionic liquids

Patent metadata

Field	Value
Publication number	US-9663386-B2
Application number	US-201214236087-A
Country	US
Kind code	B2
Filing date	Jul 31, 2012
Priority date	Aug 1, 2011
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

The present invention relates to a process for the extraction of metals from an aqueous phase by means of specific ionic liquids.

First claim

The invention claimed is:

1. A process for extraction of at least one metal from an aqueous phase, the process comprising extracting the at least one metal with an ionic liquid of general formula (I)

wherein
i) X − is an anion,
ii) n is a number from 0 to 14,
iii) R 1 and R 2 independently from each other are —H, -halogen, —NO 2 , —NH 2 , —NHR x , —N(R x ) 2 , —R x , —C(O)OH, —C(O)OR x , —C(O)R x or —OR x , wherein R x is a straight-chained or branched, substituted or unsubstituted C1 to C18 alkyl group;
wherein no additional extracting agent is used;
wherein the pH value of the aqueous phase is between 8 and 0; and
wherein the at least one metal to be extracted is selected from the group consisting of heavy metals, the group of rare earths and the group of actinides.

2. The process according to claim 1 , wherein X − is bis(trifluoromethylsulfonyl)imide or dicyanamide.

3. The process according to claim 1 , wherein n=5 to 13.

4. The process according to claim 1 , wherein R 1 is —H and R 2 is selected from the group consisting of —H, -halogen, —NO 2 , —NH 2 , —NHR x , —N(R x ) 2 , —R x , —C(O)OH, —C(O)OR x , —C(O)R x and —OR x , wherein R x is a straight-chained or branched, substituted or unsubstituted C1 to C18 alkyl group.

5. The process according to claim 1 , wherein R 1 and/or R 2 are groups with a +M-effect.

6. The process according to claim 5 , wherein R 2 is -halogen or —OR x , wherein R x is a straight-chained or branched, substituted or unsubstituted C1 to C18 alkyl group.

7. The process according to claim 1 , wherein the metal to be extracted is platinum and/or europium.

8. The process according to claim 1 , wherein the process is carried out in a pH range between 5 and 0.

9. The process according to claim 1 , wherein the extraction ratio does not decrease by more than 60% over the whole pH range.

10. The process according to claim 1 , wherein the extraction is a selective extraction of at least one metal from a mixture of at least two metals in an aqueous phase.

Assignees

• Strassner Thomas
• Schulz Tobias
• Bernhard Gert
• Raff Johannes
• Lehmann Falk
• Univ Dresden Tech
• Helmholtz-Zentrum Dresden-Rossendorf E V

Inventors

• Strassner Thomas
• Schulz Tobias
• Bernhard Gert
• Raff Johannes
• Lehmann Falk

Classifications

• B01D11/0292

  Treatment of the solvent · CPC title

• C22B60/026

  liquid-liquid extraction with or without dissolution in organic solvents · CPC title

• C01G55/001

  Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange · CPC title

• C02F1/26 Primary

  by extraction · CPC title

• C02F2101/20

  Heavy metals or heavy metal compounds · CPC title