Binding of uranyl ion by 2,2′-dihydroxyazobenzene attached to crosslinked polystyrenes covered with highly populated quaternary ammonium cations

✍ Scribed by Kwanpyo Lee; Bo-Bin Jang; Won Jong Kwon; Junghun Suh

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 166 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19991115)37:22<4117::aid-pola10>3.0.co;2-b

✦ Synopsis

2,2Ј-Dihydroxyazobenzene (DHAB) derivatives were attached to poly(chloromethylstyrene-co-divinylbenzene) (PCD) because of the high affinity of DHAB for uranyl ion. Chloromethyl groups of PCD were converted to quaternary ammonium ions by treating them with tertiary amines. Two strategies were adopted to improve the uranyl-binding ability of the immobilized DHAB: (1) the creation of a highly cationic microenvironment around the DHAB moieties and (2) the introduction of electronwithdrawing groups to DHAB. Capacity of the resins for uranyl uptake was measured, revealing that about 10 to 46 mg of uranium could be complexed to 1 g of the resins. Formation constants (K f ) for the uranyl complexes of the resins were determined. In the presence of Ն0.02 M bicarbonate ion at pH 8.02, log K f values of 14.3 to 15.8 were obtained. Uranium extraction from seawater with two kinds of resins prepared in this study was carried out on the east coast of the Korean peninsula. The amount of uranium extracted from seawater was up to 150 g/g resin. Thus, the uraniumextracting capability of the DHAB-containing polystyrene resins was improved significantly by the structural modifications.