Extraction of Cupric Ions with Ionic Liquids Containing Polypyridine‐type Small Molecules or Peripherally Pyridine‐modified Dendrimers |
| |
Authors: | Chung‐Jui Su Yi‐Hsuan Tang Fu‐Lun Yu Ru‐Rong Wu Prof Sodio C N Hsu Prof Chai‐Lin Kao Hsin‐Yi Huang Prof Po‐Yu Chen |
| |
Institution: | 1. Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, No. 100, Shih‐Chuan 1?stRoad, Kaohsiung 807 (Taiwan), Fax: (+886)?7‐3121101 ext.2587;2. The Instrument Center of National Cheng Kung University, Tainan 701 (Taiwan) |
| |
Abstract: | The hydrophobic ionic liquid N‐butyl‐N‐methylpyrrolidinium bis((trifluoromethyl)sulfonyl)amide (BMP‐TFSA IL), which contains a series of flexible ionophores of polypyridine‐type small molecules or two rigid ionophores of peripherally pyridine‐modified PAMAM dendrimers, was used to extract cupric ions from aqueous solutions. The polypyridine‐type ionophores show good selectivity toward cupric ions at pH 2. The selectivity is affected by the spacing between the two amino groups. However, the pyridine‐modified dendrimers showed poor selectivity, although their extraction efficiency still depended on the pH of the aqueous solution. The ionic liquids that contained small molecular ionophores and their dendrimer analogs were reused after acid washing or electrochemical reduction. During acid washing, the nitrogen atoms of the ionophores were protonated to release the cupric ions into the aqueous phase, and the copper atoms were deposited onto the electrode surface during the electrochemical reduction accompanied by the regeneration of the ionophores. |
| |
Keywords: | copper extraction ionic liquid reuse selectivity |
|
|